Exhibit 4.15


 


The
securities represented by this instrument have not been registered under the Securities Act of 1933, as amended, and may not be
sold, transferred, assigned, pledged, or hypothecated unless and until registered under such act, or unless the Debtor has received
an opinion of counsel or other evidence, satisfactory to the Debtor and its counsel, that such registration is not required.


 


THIS
NOTE IS ISSUED WITH ORIGINAL ISSUE DISCOUNT AS DEFINED BY SECTION 1273(a)(1) OF THE INTERNAL REVENUE CODE OF 1986, AS AMENDED.
THE FOLLOWING INFORMATION IS PROVIDED PURSUANT TO THE INFORMATION REPORTING REQUIREMENTS SET FORTH IN TREASURY REGULATION 1.1275-3.



 


UPON
WRITTEN REQUEST TO KIRK HONOUR OF TITAN CNG LLC, AT 315 LAKE STREET E., SUITE 301, WAYZATA, MN 55391 INFORMATION REGARDING THE
ISSUE PRICE, AMOUNT OF ORIGINAL ISSUE DISCOUNT, ISSUE DATE AND YIELD TO MATURITY WILL PROMPTLY BE MADE AVAILABLE.


 


THIS SECURED BRIDGE NOTE IS ONE IN
A SERIES OF SECURED BRIDGE NOTES BEING ISSUED IN CONNECTION WITH A BRIDGE FINANCING OF UP TO $1,500,000, INCLUDING, WITHOUT LIMITATION,
THOSE CERTAIN SECURED BRIDGE NOTES DATED ON OR ABOUT THE DATE HEREOF BY TITAN CNG LLC IN FAVOR OF EACH OF RED OCEAN CONSULTING,
LLC, THE Thomas J. Abood Revocable Trust u/a
dated August 17, 2012, as amended,
THE ALPETER FAMILY LIMITED PARTNERSHIP, AND JAMES JACKSON, AND ANY PAYMENTS AND ACCESS TO COLLATERAL WILL BE ON
A PARI PASSU BASIS WITH SUCH OTHER SECURED BRIDGE NOTES.


 


SECURED
BRIDGE NOTE


 





	$150,000.00	February 29, 2016
	 	Minneapolis, Minnesota




  


FOR VALUE RECEIVED,
TITAN CNG LLC, a Delaware limited liability company (the “Debtor”), promises to pay to the order of David M. Leavenworth
(“Holder”), the principal sum of $150,000.00, together with interest, in the manner provided in this Note. 


 


1.           Repayment
of Principal. All outstanding principal, if not previously paid, will be due and payable on June 28, 2016 (the “Stated
Maturity Date”).


 


2.           Interest.


 


2.1         Interest
will accrue on all outstanding unpaid amounts evidenced by this Note at an interest rate of 12% per year; provided that
if written notice is given by Holder to Debtor of the occurrence of an Event of Default (as defined below), and if Debtor fails
to cure the Event of Default within ten (10) days after receipt of such notice, the interest rate will increase to 15% per year.


 






     


     


    

 


2.2         All
interest will be computed on the basis of a 365-day year containing 12 months, counting the actual number of days in each month.
Except as otherwise provided in Section 2.4, all interest will be payable in kind on (and thereby increase) the outstanding principal
amount of this Note (as such principal is increased from time to time) until the Stated Maturity Date. All accrued interest will
be due and payable on the Stated Maturity Date.


 


2.3         In
the event that the Note is prepaid prior to the Stated Maturity Date, a minimum amount of interest equal to four months’
interest will be deemed payable under this Note.


 


2.4         Notwithstanding
anything to the contrary herein, if the aggregate amount of accrued but unpaid interest (including payable in kind interest) on
this Note and all unpaid original issue discount on this Note as of the Stated Maturity Date would, but for this provision, exceed
an amount equal to the product of:


 


(a)         the
issue price (as defined in Sections 1273(b) and 1274(a) of the Internal Revenue Code of 1986, as amended (the “Code”))
of this Note; and


 


(b)         the
yield to maturity (interpreted in accordance with Section 163(i) of the Code) of this Note (such product, the “Maximum Accrual”),


 


then
all accrued and unpaid interest (including the payable in kind interest) and original issue discount on this Note in excess of
an amount equal to the Maximum Accrual shall be paid in cash prior to the Stated Maturity Date.


 


It
is the intent of the parties that the cash payments required by this Section 2.4 will cause this Note to not be classified as
“applicable high yield discount obligations” within the meaning of Section 163(i) of the Code. To the extent that
for any reason these provisions do not accomplish this purpose, the parties may modify the payment terms in this Section 2.4 to
accomplish the purpose.


 


3.    
     Method of Payment for Principal and Interest. All payments with respect to this Note
will be made by wire transfer, in immediately available funds, to such account as Holder may specify in writing, without any
presentation of this Note. Each payment with respect to this Note will be applied (i) first, to any fees, expenses or other
amounts (other than principal and interest) due under this Note, (ii) second, to accrued interest, and (iii) third, to
outstanding principal. Whenever any payment to be made under this Note is due on a Saturday, Sunday or holiday for banks
under the laws of the State of Delaware, such payment may be made on the next succeeding bank business day, and such
extension of time will in such case be included in the computation of the amount of interest due.


 


4.   
       Equity. From and after the occurrence of any Event of Default and until such Event
of Default is remedied to the reasonable satisfaction of Holder, Debtor will issue Holder 750 Class A Membership Units (as
defined in the Amended and Restated Limited Liability Company of Debtor (the “LLC Agreement”)) on the date of
such Event of Default and each 90 day interval thereafter until all amounts due and owing under this Note have been paid in
full.


 






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5.    
      Events of Default. An “Event of Default” means any of the
following:


 


5.1         The
failure to pay any principal of, and interest on or any other amount due under this Note when and as the same will become due
and payable, whether at the due date thereof or at a date fixed for prepayment thereof or by acceleration thereof or otherwise
and such failure continues unremedied for a period of two business days.


 


5.2         A
material default by Debtor or any entity in which Debtor controls or owns a majority of the outstanding equity interest therein
(each a “Subsidiary” and collectively along with each other Subsidiary and the Debtor, the “Debtor Group”
and each individually a “Debtor Group Member”) in the performance or observance of any covenant, condition, undertaking
or agreement contained in this Note, the Security Agreement dated on or about the date hereof among Holder, other holders of notes
issued in connection herewith and the Debtor Group Members (the “Security Agreement”), or the Pledge Agreements dated
on or about the date hereof among Holder, on the one hand, and the other holders of notes issued in connection herewith (the “Pledge
Agreements”), and such default continues for a period of 30 days after notice by Holder to Debtor of such default.


 


5.3         If,
pursuant to or within the meaning of the United States Bankruptcy Code or any other federal or state law relating to insolvency
or relief of debtors (a “Bankruptcy Law”), a Debtor Group Member (a) commences a voluntary case or proceeding; (b)
consents to the entry of an order for relief against a Debtor Group Member in an involuntary case; (c) consents to the appointment
of a trustee, receiver, assignee, liquidator or similar official; (d) makes an assignment for the benefit of the creditors
of any Debtor Group Member; or (e) admits in writing Debtor Group Member’s inability to pay its debts as they become due.


 


5.4         If
a court of competent jurisdiction enters an order or decree under any Bankruptcy Law that (a) is for relief against a Debtor Group
Member in an involuntary case, (b) appoints a trustee, receiver, assignee, liquidator or similar official for Debtor or substantially
all of a Debtor Group Member’s properties, or (c) orders the liquidation of a Debtor Group Member and in each case the order
or decree is not dismissed within 90 days.


 


5.5         A
Debtor Group Member shall fail to discharge within a period of thirty (30) days after the commencement thereof any attachment,
sequestration, or similar proceeding or proceedings involving an aggregate amount in excess of One Hundred Thousand and No/100
Dollars ($100,000.00) against any of its assets or properties.


 


5.6         A
Debtor Group Member shall fail to satisfy and discharge promptly any judgment or judgments against it for the payment of money
in an aggregate amount in excess of One Hundred Thousand and No/100 Dollars ($100,000.00).


 


5.7         A
Debtor Group Member shall default in the payment of any of its indebtedness having an aggregate principal amount in excess of
One Hundred Thousand and No/100 Dollars ($100,000.00), beyond any applicable grace period, or shall default, in any material respect,
in its performance of any material agreement binding upon it or its property.


 






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6.          Remedies.


 


6.1         From
and after the occurrence of any Event of Default, Holder will be entitled to: (a) by written notice to the Debtor, declare all
indebtedness evidenced by this Note to be immediately due and payable; (b) apply any and all amounts owed to Debtor by the Holder
to the payment of this Note; (c) exercise and enforce its rights and remedies under this Note, the Security Agreement, and the
Pledge Agreements; and (d) proceed to protect and enforce its rights under applicable law.


 


6.2         No
course of dealing on the part of Holder or any delay or failure on the part of Holder to exercise any right will operate as a
waiver of such right or otherwise prejudice the Holder’s rights, powers and remedies.


 


6.3         Debtor
will pay to Holder such additional amounts as are sufficient to cover the costs and expenses, including, without limitation, reasonable
attorneys’ fees, incurred by Holder in collecting any sums due on account of this Note or otherwise in enforcing its rights
hereunder.


 


7.          Optional
Prepayments. Subject to the minimum interest payment set forth in Section 2.3, the indebtedness evidenced by this Note may
be prepaid, in whole or in part, at any time.


 


8.          General.


 


8.1         Payment
of principal or interest on this Note may only be made to, or upon the order of, the registered Holder. This Note is transferable
only by surrender of this Note to the Debtor, duly endorsed or accompanied by a written instrument of transfer executed by the
registered Holder. Upon surrender of this Note for transfer as provided above, Debtor will issue a new Note to, and register such
new Note in the name of, the transferee and such new Note must contain the same legend as provided in this Note.


 


8.2         Debtor:


 


(a)         except
as provided in Section 6, waives diligence, presentment, demand for payment, notice of dishonor, notice of non-payment, protest,
notice of protest, and any and all other demands in connection with the delivery, acceptance, performance, default or enforcement
of this Note;


 


(b)         agrees
that Holder will have the right, without notice, to grant any extension of time for payment of any indebtedness evidenced by this
Note or any other indulgence or forbearance whatsoever;


 


(c)         agrees
that no failure on the part of Holder to exercise any power, right or privilege hereunder, or to insist upon prompt compliance
with the terms of this Note, will constitute a waiver of that power, right or privilege; and


 






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(d)         agrees
that the acceptance at any time by Holder of any past due amounts will not be deemed to be a waiver of the requirement to make
prompt payment when due of any other amounts then or hereafter due and payable.


 


8.3         This
Note will be construed and enforced in accordance with the substantive laws of the State of Delaware without giving effect to
the conflicts of laws principles of any jurisdiction.


 


8.4         AT
THE OPTION OF HOLDER, THIS NOTE MAY BE ENFORCED IN ANY STATE OR FEDERAL COURT SITTING IN MINNEAPOLIS OR ST. PAUL, MINNESOTA, AND
DEBTOR CONSENTS TO THE JURISDICTION AND VENUE OF ANY SUCH COURT AND WAIVES ANY ARGUMENT THAT VENUE IN SUCH FORUMS IS NOT CONVENIENT.
IN THE EVENT DEBTOR COMMENCES AN ACTION IN ANOTHER JURISDICTION OR VENUE UNDER ANY TORT OR CONTRACT THEORY ARISING DIRECTLY OR
INDIRECTLY FROM THE RELATIONSHIP CREATED BY THIS NOTE, OR ALLEGING ANY BREACH OF THIS NOTE, HOLDER AT ITS OPTION IS ENTITLED TO
HAVE THE CASE TRANSFERRED TO ONE OF THE JURISDICTIONS AND VENUES DESCRIBED ABOVE, OR IF SUCH TRANSFER CANNOT BE ACCOMPLISHED UNDER
APPLICABLE LAW, TO HAVE SUCH CASE DISMISSED WITHOUT PREJUDICE.


 


8.5         DEBTOR
WAIVES THE RIGHT TO A TRIAL BY JURY IN ANY ACTION BASED ON OR PERTAINING TO THIS NOTE.


 


8.6         This
Note is secured by the Security Agreement and the Pledge Agreements.


 


8.7         Debtor
and Holder agree that (a) this Note and the membership interests of Debtor being issued to Holder pursuant to the Subscription
Agreement constitute an “investment unit” for purposes of Section 1273(c)(2)(A) of the Internal Revenue Code of 1986,
as amended, (b) the total issue price of the investment unit being issued to Holder is equal to the principal amount of this Note,
and (c) for tax purposes, the allocation of the total issue price among this Note and the membership interests in proportion to
its fair market value results in an original issue discount. None of the parties will take any position in its tax returns or
otherwise that is inconsistent with this paragraph.




 


8.8         The
parties acknowledge and agree that at the closing of the offering contemplated by the PPM (as defined in the Subscription and
Investment Representation Agreement dated the date hereof) (the “PPM Closing”), provided this Note is not
then in default, (a) $90,000 of the principal and accrued and unpaid interest under this Note will be converted into the
securities issued pursuant to the PPM Closing (it being understood that the resulting Class A Membership Unit Convertible Notes
shall entitle Holder to convert such note into Class A Membership Units at the lesser of the price offered to all holders thereof
or $10.00 per unit (subject to equitable adjustment for any unit splits or combinations, unit distributions or dividend or similar
transactions), and (b) the remaining balance under this Note may be converted into the securities issued pursuant to the PPM Closing
at the option of Holder under the same terms. 


 


8.9         Acknowledgement
of Bridge Financing. Holder acknowledges and agrees that (a) this Note is one in a series of Secured Bridge Notes (collectively,
the “Bridge Financing”), (b) Debtor may seek up to $1,500,000 in connection with the Bridge Financing, and (c) Holder
will exchange this Note and the documents and agreements executed in connection herewith for updated documents and agreements
that reflect any change to Holder’s pro rata percentage of the outstanding balance under the Bridge Financing.


 


8.10         Alpeter
Signature Pages. Borrower will deliver to Holder or its legal counsel the Alpeter Family Limited Partnership’s signature
pages to the Subordination Agreement dated the date hereof among Debtor, Holder and the Alpeter Family Limited Partnership by
March 4, 2016. The failure to deliver such signature pages by March 4, 2016 will constitute an Event of Default under and as defined
by this Note.


 


*
* * * *


 






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IN
WITNESS WHEREOF, Debtor has caused this Note to be signed by a duly authorized officer and dated as of the date first above written.


 


	 	 	TITAN
    CNG LLC
	 	 	 
	 	 	By:	/s/
    Kirk S. Honour
	 	 	Name:	Kirk S. Honour
	 	 	Its:	President
	 	 	 	 
	Acknowledged
    and Agreed:	 	 	 
	 	 	 	 
	/s/
    David M. Leavenworth	 	 	 
	DAVID
    M. LEAVENWORTH	 	 	 




 


 


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