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                                                                   EXHIBIT 10.99


                            STANDARD COMMERCIAL LEASE

                         ARTICLE 1.00 BASIC LEASE TERMS

1.01. PARTIES. This lease agreement ("Lease") is entered into by and between the
following Lessor and Lessee:

         Clear Lake Properties                                        ("Lessor")
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         Johnson Engineering                                          ("Lessee")
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1.02. LEASED PREMISES. In consideration of the rents, terms, provisions and
covenants of this Lease, Lessor hereby leases, lets and demises to Lessee the
following described premises ("leased premises"):

17,920 square feet of warehouse/showroom space located at

Gemini Park                                        (Name of building or project)

920 Gemini Avenue                                  (Street address/suite number)

Houston, Texas 77058                               (City, State, and Zip Code)

1.03. TERM. Subject to and upon the conditions set forth herein, the term of
this Lease shall commence on (February 1, 1998 the "commencement date"), and
shall terminate on the last day of the 36th month thereafter. Tenant to occupy
and Lease to commence December 22, 1997 at no cost until February 1, 1998.

1.04. BASE RENT AND SECURITY DEPOSIT. Base rent is $See Article 16.01 per month.
Security deposit is $7,710.00.

1.05.    ADDRESSES.

<TABLE>
<CAPTION>
          Lessor's Address:                                           Lessee's Address:
<S>                                                                <C>
Clear Lake Properties c/o The Centra Group, L.L.C.                 555 Forge River Road, #150
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1001 West Loop South, Suite 810                                    Webster, Texas  77598
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Houston, Texas  77027                                              Attn.:  William A. Jackson
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</TABLE>



1.06. PERMITTED USE. Warehouse/showroom, assembly, light manufacturing, welding,
and machine shop.

                               ARTICLE 2.00 RENT

2.01. BASE RENT. Lessee agrees to pay monthly as base rent during the term of
this Lease the sum of money set forth in section 1.04 of this Lease, which
amount shall be payable to Lessor at
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the address shown above. One monthly installment of rent shall be due and
payable on the date of execution of this Lease by Lessee for the first month's
rent and a like monthly installment shall be due and payable on or before the
first day of each calendar month succeeding the commencement date or completion
date during the term of this Lease; provided, if the commencement date or the
completion date should be a date other than the first day of a calendar month,
the monthly rental set forth above shall be prorated to the end of that calendar
month, and all succeeding installments of rent shall be payable on or before the
first day of each succeeding calendar month during the term of this Lease.
Lessee shall pay, as additional rent, all other sums due under this Lease.

2.02. OPERATING EXPENSES. In the event Lessor's operating expenses for the
building and/or project of which the leased premises are a part shall, in any
calendar year during the term of this Lease, exceed the sum of $1997 Base Year
Operating Expenses, including taxes and insurance per square foot, taxes, and
insurance. Lessee agrees to pay as additional rent lessee's pro rata share of
such excess operating expenses. Lessee occupies 17,920 square feet of space in a
project totaling 140,762 square feet (12.73%). Lessor may invoice Lessee monthly
for Lessee's pro rata share of the estimated operating expenses for each
calendar year, which amount shall be adjusted each year based upon anticipated
operating expenses. Within nine months following the close of each calendar
year, Lessor shall provide Lessee an accounting showing in reasonable detail all
computations of additional rent due under this section. In the event the
accounting shows that the total of the monthly payments made by Lessee exceeds
the amount of additional rent due by Lessee under this section, the accounting
shall be accompanied by a refund. In the event the accounting shows that the
total of the monthly payments made by Lessee is less than the amount of
additional rent due by Lessee under this section, the account shall be
accompanied by an invoice for the additional rent. Notwithstanding any other
provision in this Lease, during the year in which the Lease terminates, Lessor,
prior to the termination date, shall have the option to invoice Lessee for
Lessee's pro rata share of the excess operating expenses based upon the previous
year's operating expenses. If this Lease shall terminate on a day other than the
last day of a calendar year, the amount of any additional rent payable by Lessee
applicable to the year in which such termination shall occur shall be prorated
on the ratio that the number of days from the commencement of the calendar year
to and including the termination date bears to 365. Lessee shall have the right,
at its own expense and within a reasonable time, to audit Lessor's books
relevant to the additional rent payable under this section. Lessee agrees to pay
any additional rent due under this section within ten days following receipt of
the invoice or accounting showing additional rent due.

2.03. DEFINITION OF OPERATING EXPENSES. The term "operating expenses" includes
all expenses incurred by Lessor with respect to the maintenance and operation of
the building of which the leased premises are a part, including, but not limited
to, the following: maintenance, repair and replacement costs; security;
management fees, wages and benefits payable to employees of Lessor whose duties
are directly connected with the operation and maintenance of the building; all
services, utilities, supplies, repairs, replacements or other expenses for
maintaining and operating the common parking and plaza areas; the cost,
including interest, amortized over its useful life, of any capital improvement
made to the building by Lessor after the date of this Lease which is required
under any governmental law or regulation that was not applicable to the building
at the time it was constructed; the cost, including interest, amortized over its
useful life, of installation of any device or other equipment which improves the
operating efficiency of any


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system within the leased premises and thereby reduces operating expenses; all
other expenses which would generally be regarded as operating and maintenance
expenses which would reasonably be amortized over a period not to exceed five
years; all real property taxes and installments of special assessments,
including dues and assessments by means of deed restrictions and/or owners'
associations which accrue against the building of which the leased premises are
a part during the term of this Lease; and all insurance premiums Lessor is
required to pay or deems necessary to pay, including public liability insurance,
with respect to the building. The term operating expenses does not include the
following: repairs, restoration or other work occasioned by fire, wind, the
elements or other casualty; income and franchise taxes of Lessor; expenses
incurred in leasing to or procuring of lessees, leasing commissions, advertising
expenses and expenses for the renovating of space for new lessees; interest or
principal payments on any mortgage or other indebtedness of Lessor; compensation
paid to any employee of Lessor above the grade of property manager, any
depreciation allowance or expense; or operating expenses which are the
responsibility of Lessee.

2.04. LATE PAYMENT CHARGE. Other remedies for nonpayment of rent withstanding,
if the monthly rental payment is not received by Lessor on or before the tenth
day of the month for which the rent is due, or if any other payment due Lessor
by Lessee is not received by Lessor on or before the tenth day of the month next
following the month in which Lessee was invoiced, a late payment charge of five
percent of such past due amount shall become due and payable in addition to such
amounts owed under this Lease.

2.05. INCREASE IN INSURANCE PREMIUMS. If an increase in any insurance premiums
paid by Lessor for the building is caused by Lessee's use of the leased premises
in a manner other than as set forth in section 1.06, or if Lessee vacates the
leased premises and causes an increase in such premiums, then Lessee shall pay
as additional rent the amount of such increase to Lessor.

2.06. SECURITY DEPOSIT. The security deposit set forth above shall be held by
Lessor for the performance of Lessee's covenants and obligations under this
Lease, it being expressly understood that the deposit shall not be considered an
advance payment of rental or a measure of Lessor's damage in case of default by
Lessee. Upon the occurrence of any event of default by Lessee or breach by
Lessee of Lessee's covenants under this Lease, Lessor may, from time to time,
without prejudice to any other remedy, use the security deposit to the extent
necessary to make good any arrears of rent, or to repair any damage or injury,
or pay any expense or liability incurred by Lessor as a result of the event of
default or breach of covenant, and any remaining balance of the security deposit
shall be returned by Lessor to Lessee upon termination of this Lease. If any
portion of the security deposit is so used or applied, Lessee shall upon ten
days written notice from Lessor, deposit with Lessor by cash or cashier's check
an amount sufficient to restore the security deposit to its original amount. The
security deposit shall transfer and be the responsibility of any new Owner or
transferee.

2.07. HOLDING OVER. In the event that the Lessee does not vacate the leased
premises upon the expiration or termination of this Lease, Lessee shall be a
tenant at will for the holdover period and all of the terms and provisions of
this Lease shall be applicable during that period, except that Lessee shall pay
Lessor as base rental for the period of such holdover an amount equal to one and
one-half times the base rent which would have been payable by Lessee had the
holdover period been a part of the original term of this Lease. Lessee agrees to
vacate and deliver the


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leased premises to Lessor upon Lessee's receipt of notice from Lessor to vacate.
The rental payable during the holdover period shall be payable to Lessor on
demand. No holding over by Lessee, whether with or without the consent of
Lessor, shall operate to extend the term of this Lease.

                         ARTICLE 3.00 OCCUPANCY AND USE

3.01. USE. Lessee warrants and represents to Lessor that the leased premises
shall be used and occupied only for the purpose as set forth in section 1.06.
Lessee shall occupy the leased premises, conduct its business and control its
agents, employees, invitees and visitors in such a manner as is lawful,
reputable and will not create a nuisance. Lessee shall not permit any operation
which emits any odor or matter which intrudes into other portions of the
building, use any apparatus or machine which makes undue noise or causes
vibration in any portion of the building or otherwise interfere with, annoy or
disturb any other lessee in its normal business operations or Lessor in its
management of the building. Lessee shall neither permit any waste on the lease
premises nor allow the leased premises to be used in any way which would, in the
opinion of Lessor, be extra hazardous on account of fire or which would in any
way increase or render void the fire insurance on the building. Lessee warrants
to Lessor that the insurance questionnaire (filled out by Lessee, signed and
presented to Lessor prior to the execution of this Lease) accurately reflects
Lessee's original intended use of the leased premises. The insurance
questionnaire is made a part of this Lease by reference as though fully copied
herein. If at any time during the term of this Lease the State Board of
Insurance or other insurance authority disallows any of Lessor's sprinkler
credits or imposes any additional penalty or surcharge in Lessor's insurance
premiums because of Lessee's original or subsequent placement or use of storage
racks or bins, method of storage or nature of Lessee's inventory or any other
act of Lessee, Lessee agrees to pay as additional rent the increase (between
fire walls) in Lessor's insurance premiums.

3.02. SIGNS. No sign of any type or description shall be erected, placed or
painted in or about the leased premises or project except those signs submitted
to Lessor in writing and approved by Lessor in writing, and which signs are in
conformance with Lessor's sign criteria established for the project.

3.03. COMPLIANCE WITH LAWS, RULES AND REGULATIONS. Lessee, at Lessee's sole cost
and expense, shall comply with all laws, ordinance, orders, rules and
regulations of state, federal, municipal or other agencies or bodies having
jurisdiction over use, condition and occupancy of the leased premises. Lessee
will comply with the rules and regulations of the building adopted by Lessor
which are set forth on a schedule attached to this Lease. Lessor shall have the
right at all times to change and amend the rules and regulations in any
reasonable manner as may be deemed advisable for the safety, care, cleanliness,
preservation of good order and operation or use of the building or the lease
premises. All changes and amendments to the rules and regulations of the
building will be sent by Lessor to Lessee in writing and shall thereafter be
carried out and observed by Lessee.

3.04. WARRANTY OF POSSESSION. Lessor warrants that it has the right and
authority to execute this Lease, and Lessee, upon payment of the required rents
and subject to the terms, conditions, covenants and agreements contained in this
Lease, shall have possession of the leased premises


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during the full term of this Lease as well as any extension or renewal thereof.
Lessor shall not be responsible for the acts or omissions of any other lessee or
third party that may interfere with Lessee's use and enjoyment of the leased
premises. In the event of sale or transfer of building, Tenant's lease shall not
be disturbed.

3.05. INSPECTION. Lessor or its authorized agents shall at any and all
reasonable times have the right to enter the leased premises with reasonable
notice to inspect the same, to supply janitorial service or any other service to
be provided by Lessor, to show the leased premises to prospective purchasers or
lessees, and to alter improve or repair the leased premises or any other portion
of the building. Lessee hereby waives any claim for damages for injury or
inconvenience to or interference with Lessee's business, any loss of occupancy
or use of the leased premises, and any other loss occasioned thereby. Lessor
shall at all times have and retain a key with which to unlock all of the doors
in, upon and about the leased premises. Lessee shall not change Lessor's lock
system or in any other manner prohibit Lessor from entering the leased premises.
Lessor shall have the right to use any and all means which Lessor may deem
proper to open any door in an emergency without liability therefor.

                       ARTICLE 4.00 UTILITIES AND SERVICE

4.01. BUILDING SERVICES. Lessor shall provide the normal utility serve
connections to the building. Lessee shall pay the cost of all utility services,
including, but not limited to, initial connection charges, all charges for gas,
electricity, water, sanitary and storm sewer service, and for all electric
lights. However, in a multi-occupancy building, Lessor may provide water to the
leased premises, in which case Lessee agrees to pay to Lessor its pro rata share
of the cost of such water. Lessee shall pay all costs caused by Lessee
introducing excessive pollutants or solids other than ordinary human waste into
the sanitary sewer system, including permits, fees and charges levied by any
governmental subdivision for any such pollutants or solids. Lessee shall be
responsible for the installation and maintenance of any dilution tanks, holding
tanks, settling tanks, sewer sampling devices, sand traps, grease traps or
similar devices as may be required by any governmental subdivision for Lessee's
use of the sanitary sewer system. If the leased premises are in a
multi-occupancy building, Lessee shall pay all surcharges levied due to Lessee's
use of sanitary sewer or waste removal services insofar as such surcharges
affect Lessor or other lessees in the building. Lessor shall not be required to
pay for any utility services, supplies or upkeep in connection with the leased
premises or building.

4.02. THEFT OR BURGLARY. Lessor shall not be liable to Lessee for losses to
Lessee's property or personal injury caused by criminal acts or entry by
unauthorized persons into the leased premises or the building.

                      ARTICLE 5.00 REPAIRS AND MAINTENANCE

5.01. LESSOR REPAIRS. Lessor shall not be required to make any improvements,
replacements or repairs of any kind or character to the leased premises or the
project during the term of this Lease except as are set forth in this section.
Lessor shall maintain only the roof, foundation, parking and common areas, and
the structural soundness of the exterior walls (excluding windows, window glass,
plate glass and doors). Lessor's costs of maintaining the items set forth in
this section are subject to the additional rent provisions in section 2.02.
Lessor shall not be


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liable to Lessee, except as expressly provided in this Lease, for any damage or
inconvenience; and Lessee shall not be entitled to any abatement or reduction of
rent by reason of any repairs, alterations or additions made by Lessor under
this Lease. Roof shall be free of any leakage upon Tenant's occupancy or a
reasonable time thereafter.

5.02. LESSEE REPAIRS. Lessee shall, at its sole cost and expense, maintain,
repair and replace all other parts of the leased premises in good repair and
condition, including, but not limited to, heating, ventilating and air
conditioning systems, down spouts, fire sprinkler system, dock bumpers, lawn
maintenance, pest control and extermination, trash pick-up and removal, and
painting the building and exterior doors. Lessee shall repair and pay for any
damage caused by any act or omission of Lessee or Lessee's agents, employees,
invitees, licensees or visitors. If the leased premises are in a multi-occupancy
building or project, Lessor shall perform, on behalf of Lessee, lawn
maintenance, painting, and trash pick-up and removal; Lessee agrees to pay
Lessor, as additional rent, Lessee's pro rata share of the cost of such services
within ten days from receipt of lessor's invoice, or Lessor may by monthly
invoice direct Lessee to prepay the estimated costs for the current calendar
year, and such amount shall be adjusted annually. If the leased premises are
served by rail, Lessee agrees, if requested by the railroad, to enter into a
joint maintenance agreement with the railroad and bear its pro rata share of the
cost of maintaining the railroad ____. If Lessee fails to make the repairs or
replacements promptly as required herein, Lessor may, at its option, make the
repairs and replacements and the cost of such repairs and replacements shall be
charged to Lessee as additional rent and shall become due and payable by Lessee
within ten days from receipt of Lessor's invoice. Costs incurred under this
section are the total responsibility of Lessee and do not constitute operating
expense under section 2.02.

5.03. REQUEST FOR REPAIRS. All requests for repairs or maintenance that are the
responsibility of Lessor pursuant to any provision of this Lease must be made in
writing to Lessor at the address in section 1.05. If Landlord does not repair
within a reasonable time, Tenant shall make repairs and seek reimbursement from
Landlord or offset future rent due.

5.04. LESSEE DAMAGES. Lessee shall not allow any damage to be committed on any
portion of the leased premises or building, and at the termination of this
Lease, by lapse of time or otherwise, Lessee shall deliver the leased premises
to Lessor in as good condition as existed at the commencement date of this
Lease, ordinary wear and tear excepted. The cost and expense of any repairs
necessary to restore the condition of the leased premises shall be borne by
Lessee.

5.05. MAINTENANCE CONTRACT. Lessee shall, at its sole cost and expense, during
the term of this Lease maintain a regularly scheduled preventative maintenance
service contract with a maintenance contractor for the servicing of all hot
water, heating and air conditioning systems and equipment within the leased
premises. The maintenance contractor and contract must be approved by Lessor and
must include all services suggested by the equipment manufacturer.

                   ARTICLE 6.00 ALTERATIONS AND IMPROVEMENTS

6.01. LESSOR IMPROVEMENTS. If construction to the leased premises is to be
performed by Lessor prior to or during Lessee's occupancy, Lessor will complete
the construction of the improvements to the leased premises, in accordance with
plans and specifications agreed to by Lessor and Lessee, which plans and
specifications are made a part of this Lease by reference.


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Lessee shall execute a copy of the plans and specifications and change orders,
if applicable, setting forth the amount of any costs to be borne by Lessee
within seven days of receipt of the plans and specifications. In the event
Lessee fails to execute the plans and specifications and change order within the
seven day period, Lessor may, at its sole option, declare this Lease cancelled
or notify Lessee that the base rent shall commence on the completion date even
though the improvements to be constructed by Lessor may not be complete. Any
changes or modifications to the approved plans and specifications shall be made
and accepted by written change order or agreement signed by Lessor and Lessee
and shall constitute an amendment to this Lease.

6.02. LESSEE IMPROVEMENTS. Lessee shall not make or allow to be made any
alterations or physical additions in or to the leased premises without first
obtaining the written consent of Lessor. Any alterations, physical additions or
improvements to the leased premises made by Lessee shall at once become the
property of Lessor and shall be surrendered to Lessor upon the termination of
this Lease; provided, however, Lessor, at its option, may require Lessee to
remove any physical additions and/or repair any alterations in order to restore
the leased premises to the condition existing at the time Lessee took
possession, all costs and removal and/or alterations to be borne by Lessee. This
clause shall not apply to moveable equipment or furniture owned by Lessee, which
may be removed by Lessee at the end of the term of this Lease if Lessee is not
then in default and if such equipment and furniture are not then subject to any
other rights, liens and interest of Lessor.

                      ARTICLE 7.00 CASUALTY AND INSURANCE

7.01. SUBSTANTIAL DESTRUCTION. If the leased premises should be totally
destroyed by fire or other casualty, or if the leased premises should be damaged
so that rebuilding cannot reasonably be completed within ninety working days
after the date of written notification by Lessee to Lessor of the destruction,
this Lease shall terminate and the rent shall be abated for the unexpired
portion of the Lease, effective as of the date of the written notification.

7.02. PARTIAL DESTRUCTION. If the leased premises should be partially damaged by
fire or other casualty, and rebuilding or repairs can reasonably be completed
within ninety working days from the date of written notification by Lessee to
Lessor of the destruction, this Lease shall not terminate, and Lessor shall at
its sole risk and expense proceed with reasonable diligence to rebuild or repair
the building or other improvements to substantially the same condition in which
they existed prior to the damage. If the leased premises are to be rebuilt or
repaired and are untenantable in whole or in part following the damage, and the
damage or destruction was not caused or contributed to by act or negligence of
Lessee, its agents, employees, invitees or those for whom Lessee is responsible,
the rent payable under this Lease during the period for which the leased
premises are untenantable shall be adjusted to such an extent, as may be fair
and reasonable under the circumstances. In the event that Lessor fails to
complete the necessary repairs or rebuilding within ninety working days from the
date of written notification by Lessee to Lessor of the destruction, Lessee may
at its option terminate this Lease by delivering written notice of termination
to Lessor, whereupon all rights and obligations under this Lease shall cease to
exist.


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7.03. PROPERTY INSURANCE. Lessor shall at all times during the term of this
Lease maintain a policy or policies of insurance with the premiums paid in
advance, issued by and binding upon some solvent insurance company, insuring the
building against all risk of direct physical loss in an amount equal to at least
ninety percent of the full replacement cost of the building structure and its
improvements as of the date of the loss; provided, Lessor shall not be obligated
in any way or manner to insure any personal property (including, but not limited
to, any furniture, machinery, goods or supplies) of Lessee upon or within the
leased premises, any fixtures installed or paid for by Lessee upon or within the
leased premises, or any improvements which Lessee may construct on the leased
premises. Lessee shall have no right in or claim to the proceeds of any policy
of insurance maintained by Lessor even if the cost of such insurance is borne by
Lessee as set forth in article 2.00.

7.04. WAIVER OF SUBROGATION. Anything in this Lease to the contrary
notwithstanding, Lessor and Lessee hereby waives and release each other of and
from any and all right of recovery, claim, action or cause of action, against
each other, their agents, officers and employees, for any loss or damage that
may occur to the leased premises, improvements to the building of which the
leased premises are a part, or personal property within the building, by reason
of fire or the elements, regardless of cause or origin, including negligence of
Lessor or Lessee and their agents, officers and employees. Lessor and Lessee
agree immediately to give their respective insurance companies which have issued
policies of insurance covering all risk of direct physical loss, written notice
of the terms of the mutual waivers contained in this section, and to have the
insurance policies properly endorsed, if necessary, to prevent the invalidation
of the insurance coverages by reason of the mutual waivers.

7.05. HOLD HARMLESS. Lessor shall not be liable to Lessee's employees, agents,
invitees, licensees, or to any other person, for an injury to person or damage
to property on or about the leased premises caused by any act or omission of
Lessee, its agents, servants or employees, or of any other person entering upon
the leased premises under express or implied invitation by Lessee, or caused by
the improvements located on the leased premises becoming out of repair, the
failure or cessation of any service provided by Lessor (including security
service and devices), or caused by leakage of gas, oil, water or steam or by
electricity emanating from the leased premises. Lessee agrees to indemnify and
hold harmless Lessor of and from any loss, attorney's fees, expenses or claims
arising out of any such damage or injury.

                           ARTICLE 8.00 CONDEMNATION

8.01. SUBSTANTIAL TAKING. If all or a substantial part of the leased premises
are taken for any public or quasi-public use under any governmental law,
ordinance or regulation, or by right of eminent domain or by purchase in lieu
thereof, and the taking would prevent or materially interfere with the use of
the leased premises for the purpose for which it is then being used, this Lease
shall terminate and the rent shall be abated during the unexpired portion of
this Lease effective on the date physical possession is taken by the condemning
authority. Lessee shall have no claim to the condemnation award or proceeds in
lieu thereof.

8.02. PARTIAL TAKING. If a portion of the leased premises shall be taken for any
public or quasi-public use under any governmental law, ordinance or regulation,
or by right of eminent domain or by purchase in lieu thereof, and this Lease is
not terminated as provided in section 8.01 above,


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Lessor shall at Lessor's sole risk and expense, restore and reconstruct the
building and other improvements on the leased premises to the extent necessary
to make it reasonably tenantable. The rent payable under this Lease during the
unexpired portion of the term shall be adjusted to such an extent as may be fair
and reasonable under the circumstances. Lessee shall have no claim to the
condemnation award or proceeds in lieu thereof.

                      ARTICLE 9.00 ASSIGNMENT OR SUBLEASE

9.01. LESSOR ASSIGNMENT. Lessor shall have the right to sell, transfer or
assign, in whole or in part, its rights and obligations under this Lease and in
the building. Any such sale, transfer or assignment shall operate to release
Lessor from any and all liabilities under this Lease arising after the date of
such sale, assignment or transfer, except Security Deposit shall be transferred
to the new party.

9.02. LESSEE ASSIGNMENT. Lessee shall not assign, in whole or in part, this
Lease, or allow it to be assigned, in whole or in part, by operation of law or
otherwise (including without limitation by transfer of a majority interest of
stock, merger, or dissolution, which transfer of majority interest of stock,
merger or dissolution shall be deemed an assignment) or mortgage or pledge the
same, or sublet the leased premises, in whole or in part, without the prior
written consent of Lessor, and in no event shall any such assignment or sublease
ever release Lessee or any guarantor from any obligation or liability hereunder.
No assignee or sublessee of the leased premises or any portion thereof may
assign or sublet the leased premises or any portion thereof. Landlord shall not
unreasonably withhold consent to Sublease.

9.03. CONDITIONS OF ASSIGNMENT. If Lessee desires to assign or sublet all or any
part of the leased premises to an outside third party, it shall so notify Lessor
at least thirty days in advance of the date on which Lessee desires to make such
assignment or sublease. Lessee shall provide Lessor with a copy of the proposed
assignment or sublease and such information as Lessor might request concerning
the proposed sublessee or assignee to allow Lessor to make informed judgments as
to the financial condition, reputation, operations and general desirability of
the proposed sublessee or assignee. Within fifteen days after Lessor's receipt
of Lessee's proposed assignment or sublease and all required information
concerning the proposed sublessee or assignee, Lessor shall have the following
options: (1) cancel this Lease as to the leased premises or portion thereof
proposed to be assigned or sublet; (2) consent to the proposed assignment or
sublease, and, if the rent due and payable by any assignee or sublessee under
any such permitted assignment or sublease (or a combination of the rent payable
under such assignment or sublease plus any bonus or any other consideration or
any payment incident thereto) exceeds the rent payable under this Lease for such
space, Lessee shall pay to Lessor all such excess rent and other excess
consideration within ten days following receipt thereof by Lessee; or (3)
refuse, with reasonable cause, to consent to the proposed assignment or
sublease, which refusal shall be deemed to have been exercised unless Lessor
gives Lessee written notice providing otherwise. Upon the occurrence of an event
of default, if all or any part of the leased premises are then assigned or
sublet, Lessor, in addition to any other remedies provided by this Lease or
provided by law, may, at its option, collect directly from the assignee or
sublessee all rents becoming due to Lessee by reason of the assignment or
sublease, and Lessor shall have a security interest in all properties on the
leased premises to secure payment of such sums. Any collection directly by


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Lessor from the assignee or sublessee shall not be construed to constitute a
novation or a release of Lessee or any guarantor from the further performance of
its obligations under this Lease.

9.04. RIGHTS OF MORTGAGEE. Lessee accepts this Lease subject and subordinate to
any recorded mortgage or deed of trust lien presently existing or hereafter
created upon the building or project and to all existing recorded restrictions,
covenants, easements and agreements with respect to the building or project.
Lessor is hereby irrevocably vested with full power and authority to subordinate
Lessee's interest under this Lease to any first mortgage or deed of trust lien
hereafter placed on the leased premises, and Lessee agrees upon demand to
execute additional instruments subordinating this Lease as Lessor may require.
If the interest of Lessor under this Lease shall be transferred by reason of
foreclosure or other proceedings for enforcement of any first mortgage or deed
of trust on the leased premises, Lessee shall be bound to the transferee
(sometimes called the "Purchaser") at the option of the Purchaser, under the
terms, covenants and conditions of this Lease for the balance of the term
remaining, including any extensions or renewals, with the same force and effect
as if the Purchaser were Lessor under this Lease, and, if requested by the
Purchaser, Lessee agrees to attorn to the Purchaser, including the first
mortgagee under any such mortgage if it be the Purchaser, as its Lessor.

9.05. ESTOPPEL CERTIFICATES. Lessee agrees to furnish, from time to time, within
ten days after receipt of a request from Lessor or Lessor's mortgagee, a
statement certifying, if applicable, the following: Lessee is in possession of
the leased premises; the leased premises are acceptable; the Lease is in full
force and effect; the Lease is unmodified; Lessee claims no present charge,
lien, or claim of offset against rent; the rent is paid for the current month,
but is not prepaid for more than one month and will not be prepaid for more than
one month in advance; there is no existing default by reason of some act or
omission by Lessor; and such other matters as may be reasonably required by
Lessor or Lessor's mortgagee. Lessee's failure to deliver such statement, in
addition to being a default under this Lease, shall be deemed to establish
conclusively that this Lease is in full force and effect except as declared by
Lessor, that Lessor is not in default of any of its obligations under this
Lease, and that Lessor has not received more than one month's rent in advance.

                              ARTICLE 10.00 LIENS

10.01. LANDLORD'S LIEN. As security for payment of rent, damages and all other
payments required to be made by this Lease, Lessee hereby grants to Lessor a
lien upon all property of Lessee now or subsequently located upon the leased
premises. If Lessee abandons or vacates any substantial portion of the leased
premises or is in default in the payment of any rentals, damages or other
payments required to be made by this Lease or is in default of any other
provision of this Lease, Lessor may enter upon the leased premises, by picking
or changing locks if necessary, and take possession of all or any part of the
personal property, and may sell all or any part of the personal property at a
public or private sale, in one or successive sales, with or without notice, to
the highest bidder for cash, and, on behalf of Lessee, sell and convey all or
part of the personal property to the highest bidder, delivering to the highest
bidder all of Lessee's title and interest in the personal property sold. The
proceeds of the sale of the personal property shall be applied by Lessor toward
the reasonable costs and expenses of the sale, including attorney's fees, and
then toward the payment of all sums then due by Lessee to Lessor under the terms
of


                                       10
<PAGE>   11
this Lease. Any excess remaining shall be paid to Lessee or any other person
entitled thereto by law.

10.02. UNIFORM COMMERCIAL CODE. This Lease is intended as and constitutes a
security agreement within the meaning of the Uniform Commercial Code of the
state in which the leased premises are situated. Lessor, in addition to the
rights prescribed in this Lease, shall have all of the rights, titles, liens and
interests in and to Lessee's property, now or hereafter located upon the leased
premises, which may be granted a secured party, as that term is defined, under
the Uniform Commercial Code to secure to Lessor payment of all sums due and the
full performance of all Lessee's covenants under this Lease. Lessee will on
request execute and deliver to Lessor a financing statement for the purpose of
perfecting Lessor's security interest under this Lease or Lessor may file this
Lease or a copy thereof as a financing statement. Unless otherwise provided by
law and for the purpose of exercising any right pursuant to this section, Lessor
and Lessee agree that reasonable notice shall be met if such notice is given by
ten days written notice, certified mail, return receipt requested, to Lessor or
Lessee at the addresses specified herein.

10.03. LANDLORD'S LIEN. Landlord's lien shall subordinate to Tenant's first
lienholders and shall not apply to contents owned by outside parties.

                       ARTICLE 11.00 DEFAULT AND REMEDIES

11.01. DEFAULT BY LESSEE. The following shall be deemed to be events of default
by Lessee under this Lease: (1) Lessee shall fail to pay when due any
installment of rent or any other payment required pursuant to this Lease; (2)
Lessee shall abandon any substantial portion of the leased premises; (3) Lessee
shall fail to comply with any term, provision or covenant of this Lease, other
than the payment of rent, and the failure is not cured within ten days after
written notice to Lessee; (4) Lessee shall file a petition or be adjudged
bankrupt or insolvent under any applicable federal or state bankruptcy or
insolvency law or admit that it cannot meet its financial obligations as they
become due; or a receiver or trustee shall be appointed for all or substantially
all of the assets of Lessee; or Lessee shall make a transfer in fraud of
creditors or shall make an assignment for the benefit of creditors; or (5)
Lessee shall do or permit to be done any act which results in a lien being filed
against the leased premises or the building and/or project of which the leased
premises are a part.

11.02. REMEDIES FOR LESSEE'S DEFAULT. Upon the occurrence of any event of
default set forth in this Lease, Lessor shall have the option to pursue any one
or more of the remedies set forth herein without any notice or demand. (1)
Lessor may enter upon and take possession of the leased premises, by picking or
changing locks if necessary, and lock out, expel or remove Lessee and any other
person who may be occupying all or any part of the leased premises without being
liable for any claim for damages, and relet the leased premises on behalf of
Lessee and receive the rent directly by reason of the reletting. Lessee agrees
to pay Lessor on demand any deficiency that may arise by reason of any reletting
of the leased premises; further, Lessee agrees to reimburse Lessor for any
expenditures made by it in order to relet the leased premises, including, but
not limited to, remodeling and repair costs. (2) Lessor may enter upon the
leased premises, by picking or changing locks if necessary, without being liable
for any claim for damages, and do whatever Lessee is obligated to do under the
terms of this Lease. Lessee agrees to reimburse Lessor on demand for any
expenses which Lessor may incur in effecting


                                       11
<PAGE>   12
compliance with Lessee's obligations under this Lease; further, Lessee agrees
that Lessor shall not be liable for any damages resulting to Lessee from
effecting compliance with Lessee's obligations under this Lease caused by the
negligence of Lessor or otherwise. (3) Lessor may terminate this Lease, in which
event Lessee shall immediately surrender the leased premises to Lessor, and if
Lessee fails to surrender the leased premises, Lessor may, without prejudice to
any other remedy which it may have for possession or arrearages in rent, enter
upon and take possession of the leased premises, by picking or changing locks if
necessary, and lock out, expel or remove Lessee and any other person who may be
occupying all or any part of the lease premises without being liable for any
claim for damages. Lessee agrees to pay on demand the amount of all loss and
damage which Lessor may suffer by reason of the termination of this Lease under
this section, whether through inability to relet the leased premises on
satisfactory terms or otherwise. Notwithstanding any other remedy set forth in
this Lease, in the event Lessor has made rent concessions of any type or
character, or waived any base rent, and Lessee fails to take possession of the
leased premises on the commencement or completion date or otherwise defaults at
any time during the term of this Lease, the rent concessions, including any
waived base rent, shall be cancelled and the amount of the base rent or other
rent concessions shall be due and payable immediately as if no rent concessions
or waiver of any base rent had ever been granted. A rent concession or waiver of
the base rent shall not relieve Lessee of any obligation to pay any other charge
due and payable under this Lease including without limitation any sum due under
section 2.02. Notwithstanding anything contained in this Lease to the contrary,
this Lease may be terminated by Lessor only by mailing or delivering written
notice of such termination to Lessee, and no other act or omission of Lessor
shall be construed as a termination of this Lease.

                           ARTICLE 12.00 DEFINITIONS

12.01. ABANDON. "Abandon" means the vacating of all or a substantial portion of
the leased premises by Lessee, whether or not Lessee is in default of the rental
payments due under this Lease.

12.02. ACT OF GOD OR FORCE MAJEURE. An "act of God" or "force majeure" is
defined for purposes of this Lease as strikes, lockouts, sit downs, material or
labor restrictions by any governmental authority, unusual transportation delays,
riots, floods, washouts, explosions, earthquakes, fire, storms, weather
(including wet grounds or inclement weather which prevents construction), acts
of the public enemy, wars, insurrections and any other cause not reasonably
within the control of Lessor and which by the exercise of due diligence Lessor
is unable, wholly or in part, to prevent or overcome.

12.03. BUILDING OR PROJECT. "Building" or "project" as used in this Lease means
the building and/or project described in section 1.02, including the leased
premises and the land upon which the building or project is situated.

12.04. COMMENCEMENT DATE. "Commencement date" shall be the date set forth in
section 1.03. The commencement date shall constitute the commencement of the
term of this Lease for all purposes, whether or not Lessee has actually taken
possession.


                                       12
<PAGE>   13
12.05. COMPLETION DATE. "Completion Date" shall be the date on which the
improvements erected and to be erected upon the leased premises shall have been
completed in accordance with the plans and specifications described in article
6.00. The completion date shall constitute the commencement of the term of this
Lease for all purposes, whether or not Lessee has actually taken possession.
Lessor shall use its best efforts to establish the completion date as the date
set forth in section 1.03. In the event that the improvements have not in fact
been completed as of that date, Lessee shall notify Lessor in writing of its
objections. Lessor shall have a reasonable time after delivery of the notice in
which to take such corrective action as may be necessary and shall notify Lessee
in writing as soon as it deems such corrective action has been completed and the
improvements are ready for occupancy. Upon completion of construction, Lessee
shall deliver to Lessor a letter accepting the leased premises as suitable for
the purposes for which they are let and the date of such letter shall constitute
the commencement of the term of this Lease. Whether or not Lessee has executed
such letter of acceptance, taking possession of the leased premises by Lessee
shall be deemed to establish conclusively that the improvements have been
completed in accordance with the plans and specifications, are suitable for the
purposes for which the leased premises are let, and that the leased premises are
in good and satisfactory condition as of the date possession was so taken by
Lessee, except for latent defects, if any.

12.06. SQUARE FEET. "Square feet" or "square foot" as used in this Lease
includes the area contained within the leased premises.

                          ARTICLE 13.00 MISCELLANEOUS

13.01. WAIVER. Failure of Lessor to declare an event of default immediately upon
its occurrence, or delay in taking any action in connection with an event of
default, shall not constitute a waiver of the default, but Lessor shall have the
right to declare the default at any time and take such action as is lawful or
authorized under this Lease. Pursuit of any one or more of the remedies set
forth in article 11.00 above shall not preclude pursuit of any one or more of
the other remedies provided elsewhere in this Lease or provided by law, nor
shall pursuit of any remedy constitute forfeiture or waiver of any rent or
damages accruing to Lessor by reason of the violation of any of the terms,
provisions or covenants of this Lease. Failure by Lessor to enforce one or more
of the remedies provided upon an event of default shall not be deemed or
construed to constitute a waiver of the default or of any other violation or
breach of any of the terms, provisions and covenants contained in this Lease.

13.02. ACT OF GOD. Lessor shall not be required to perform any covenant or
obligation in this Lease, or be liable in damages to Lessee, so long as the
performance or non-performance of the covenant of obligation is delayed, caused
or prevented by an act of God, force majeure or by Lessee.

13.03. ATTORNEY'S FEES. In the event Lessee defaults in the performance of any
of the terms, covenants, agreements or conditions contained in this Lease and
Lessor places in the hands of an attorney the enforcement of all or any part of
this Lease, the collection of any rent due or to become due or recovery of the
possession of the lease premises, Lessee agrees to pay Lessor's costs of
collection, including reasonable attorney's fees for the services of the
attorney, whether suit is actually filed or not.


                                       13
<PAGE>   14
13.04. SUCCESSORS. This Lease shall be binding upon and inure to the benefit of
Lessor and Lessee and their respective heirs, personal representatives,
successors and assigns. It is hereby convenanted and agreed that should Lessor's
interest in the leased premises cease to exist for any reason during the term of
this Lease, then notwithstanding the happening of such event this Lease
nevertheless shall remain unimpaired and in full force and effect, and Lessee
hereunder agrees to attorn to the then owner of the leased premises.

13.05. RENT TAX. If applicable in the jurisdiction where the leased premises are
situated, Lessee shall pay and be liable for all rental, sales and use taxes or
other similar taxes, if any, levied or imposed by any city, state, county or
other governmental body having authority, such payments to be in addition to all
other payments required to be paid to Lessor by Lessee under the terms of this
Lease. Any such payment shall be paid concurrently with the payment of the rent,
additional rent, operating expenses or other charge upon which the tax is based
as set forth above.

13.06. CAPTIONS. The captions appearing in this Lease are inserted only as a
matter of convenience and in no way define, limit, construe or describe the
scope or intent of any section.

13.07. NOTICE. All rent and other payments required to be made by Lessee shall
be payable to Lessor at the address set forth in section 1.05. All payments
required to be made by Lessor to Lessee shall be payable to Lessee at the
address set forth in section 1.05, or at any other address within the United
States as Lessee may specify from time to time by written notice. Any notice or
document required or permitted to be delivered by the terms of this Lease shall
be deemed to be delivered (whether or not actually received) when deposited in
the United States Mail, postage prepaid, certified mail, return receipt
requested, addressed to the parties at the respective addresses set forth in
section 1.05.

13.08. SUBMISSION OF LEASE. Submission of this Lease to Lessee for signature
does not constitute a reservation of space or an option to lease. This Lease is
not effective until execution by and delivery to both Lessor and Lessee.

13.09. CORPORATE AUTHORITY. If Lessee executes this Lease as a corporation, each
of the persons executing this Lease on behalf of Lessee does hereby personally
represent and warrant that Lessee is a duly authorized and existing corporation,
that Lessee is qualified to do business in the state in which the leased
premises are located, that the corporation has full right and authority to enter
into this Lease, and that each person signing on behalf of the corporation is
authorized to do so. In the event any representation or warranty is false, all
persons who execute this Lease shall be liable, individually, as Lessee.

13.10. SEVERABILITY. If any provision of this Lease or the application thereof
to any person or circumstance shall be invalid or unenforceable to any extent,
the remainder of this Lease and the application of such provisions to other
persons or circumstances shall not be affected thereby and shall be enforced to
the greatest extent permitted by law.

13.11. LESSOR'S LIABILITY. If Lessor shall be in default under this Lease and,
if as a consequence of such default, Lessee shall recover a money judgment
against Lessor, such judgment shall be satisfied only out of the right, title
and interest of Lessor in the building as the same may then be encumbered and
neither Lessor nor any person or entity comprising Lessor shall be liable for
any


                                       14
<PAGE>   15
deficiency. In no event shall Lessee have the right to levy execution against
any property of Lessor nor any person or entity comprising Lessor other than its
interest in the building as herein expressly provided.

13.12. INDEMNITY. Lessor agrees to indemnify and hold harmless Lessee from and
against any liability or claim, whether meritorious or not, arising with respect
to any broker, except Tenant's Broker Zann Commercial Brokerage, Inc., which
shall be paid a three percent (3%) commission, whose claim arises by, through or
on behalf of Lessor. Lessee agrees to indemnify and hold harmless Lessor from
and against any liability or claim, whether meritorious or not, arising with
respect to any broker whose claim arises by, through or on behalf of Lessee.

              ARTICLE 14.00 AMENDMENT AND LIMITATION OF WARRANTIES

14.01. ENTIRE AGREEMENT. IT IS EXPRESSELY AGREED BY LESSEE, AS A MATERIAL
CONSIDERATION FOR THE EXECUTION OF THIS LEASE, THAT THIS LEASE, WITH THE
SPECIFIC REFERENCES TO WRITTEN EXTRINSIC DOCUMENTS, IS THE ENTIRE AGREEMENT OF
THE PARTIES; THAT THERE ARE, AND WERE, NO VERBAL REPRESENTATIONS, WARRANTIES,
UNDERSTANDINGS, STIPULATIONS, AGREEMENTS OR PROMISES PERTAINING TO THIS LEASE OR
TO THE EXPRESSLY MENTIONED WRITTEN EXTRINSIC DOCUMENTS NOT INCORPORATED IN
WRITING IN THIS LEASE.

14.02. AMENDMENT. THIS LEASE MAY NOT BE ALTERED, WAIVED, AMENDED OR EXTENDED
EXCEPT BY AN INSTRUMENT IN WRITING SIGNED BY LESSOR AND LESSEE.

14.03. LIMITATION OF WARRANTIES. LESSOR AND LESSEE EXPRESSELY AGREE THAT THERE
ARE AND SHALL BE NO IMPLIED WARRANTIES OF MERCHANTABILITY, HABITABILITY, FITNESS
FOR A PARTICULAR PURPOSE OR OF ANY OTHER KIND ARISING OUT OF THIS LEASE, AND
THERE ARE NO WARRANTIES WHICH EXTEND BEYOND THOSE EXPRESSELY SET FORTH IN THIS
LEASE.

                         ARTICLE 15.00 OTHER PROVISIONS

15.01.   MONTHLY RENTAL SCHEDULE.  2-01-98 - 1-31-2001
$8064.00\Month

15.02.   EXHIBIT "A": - SITE PLAN

15.03.   EXHIBIT "B" - SPACE PLAN

15.04.   EXHIBIT "C" - LANDLORD'S IMPROVEMENTS

15.05.   BUILDING RULES AND REGULATIONS.  SEE ATTACHED.


                                       15
<PAGE>   16
15.06. Tenant shall have Two (2), Two (2) year options to renew lease at a
negotiated market rate. Tenant shall give Landlord ninety (90) days written
notice prior to end of lease term to exercise said renewal options.

15.07. Landlord shall provide a courtesy notification of any contiguous space,
which becomes available during this lease.

15.08. Tenant shall be permitted to occupy the leased premises before
commencement date and upon full execution of the Lease document. (See Clause
1.03)

                            ARTICLE 16.00 SIGNATURES

SIGNED at   Houston  this   22   day of     December    ,1997


      LESSOR                                                      LESSEE

Clear Lake Properties                          Johnson Engineering, Inc.
-----------------------------                  --------------------------------

By:                                            By:
-----------------------------                  --------------------------------

-----------------------------                  --------------------------------
(Type Name and Title)                          (Type Name and Title)


                                       16
<PAGE>   17
                            FIRST AMENDMENT TO LEASE

         WHEREAS, CLEAR LAKE PROPERTIES as "Lessor" and Johnson Engineering as
"Lessee" entered into that certain lease agreement (the "Lease Agreement") dated
December 22, 1997 covering approximately 17,920 square feet of net rentable
space known as 920 Gemini-Building B; and

         WHEREAS, Lessor and Lessee desire to amend the Lease Agreement and
extend the Lease Agreement;

                                                WITNESSETH

         WHEREAS, Lessor and Lessee hereby amend the Lease Agreement as follows:

                                                AGREEMENT

         NOW, THEREFORE, for and in consideration of the covenants and mutual
benefits to be derived by the parties hereto for; the matter set forth herein,
and for other good and valuable consideration, Lessor and Lessee agree as
follows:

                                        I

         IT IS AGREED that the Leased Premises will be expanded to include Suite
926 and Suite 928 Gemini containing approximately 4,531 and 8992 square feet
respectively for a total Leased Premises of 31,443 square feet.

                                       II

         IT IS FURTHER AGREED that Lessor will provide Lessee with build out
allowance in the amount of only $21,358.00 to be used toward on (1) fifteen (15)
ton HVAC installed in Suite 920, together with attending electrical wiring and
insulation of R-10 factor, as well as other improvements in Suite 920, 926 and
in 928 ("Improvements"). Lessee will use good faith efforts to have the
Improvements completed by April 30, 1999. Lessor shall cooperate with Lessee or
Lessee's agent as may be necessary to complete the Improvements.

         Lessee, through Lessee's contractor(s), will construct the
Improvements. Once the Improvements are substantially complete, Lessee will
submit to Lessor a copy of the contractor's invoice. Lessor will then have the
option of inspecting the Leased Premises to insure that the Improvements, in
Lessor's reasonable judgment, have been completed. Lessor will then pay to
Lessee's contractor (which payment will be made within thirty (30) days) the
amount of any and all invoices up to $21,358.00. If the actual amount of
invoices total more than $21,358.00, Lessee will pay the excess amount.

                                       III

         IT IS FURTHER AGREED that Lessee will deposit and additional $6,753.78
as security deposit, making the security deposit by Lessee a total of
$14,463.78.


                                       1
<PAGE>   18
                            FIRST AMENDMENT TO LEASE

                                       IV

         IT IS FURTHER AGREED that the Lease shall be extended by fifteen (15)
months from the expiration of the Lease Agreement to expire on April 30, 2002.

                                        V

         IT IS FURTHER AGREED that the new monthly Base Rent will be as follows:

         11/01/1998 Thru 10/03/2000 = $14,149.35 or $0.45 per sq. ft. per month.
         11/01/2000 Thru 04/30/2002 = $14,463.78 or $0.46 per sq. ft. per month.

                                       VI

         IT IS FURTHER AGREED that Lessor will warrant the existing HVAC in
Suite 928 through April 30, 1999.

                                       VII

         IT IS FURTHER AGREED that all the terms of the Lease Agreement shall
remain in full force and effect, according to the terms thereof. Lessor and
Lessee hereby ratify and confirm the Lease Agreement and expressly acknowledge
that the Lease Agreement, as modified by this First Amendment, represents the
entire agreement between Lessor and Lessee. Lessee expressingly acknowledges
that Lessee knows of no default on the part of Lessor that would otherwise
affect the rights and obligations of the parties under the Lease Agreement.
Lessee further acknowledges and agrees that Lessor nor Lessor's agents has not
made and is not making any warranties, representations, promises or statements,
except to the extent that the same are expressly set forth in the Lease
Agreement and this document.

         EXECUTED, in multiple and counterparts, each of which shall have the
full force and affect.

LESSOR:                                          LESSEE:
Clear Lake Properties                            Johnson Engineering

By: ________________________                     By: ___________________________


                                       2