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                                                                     EXHIBIT 4.3

REGISTERED                                                      PRINCIPAL AMOUNT
No.:                                                           $

CUSIP No.: _________

                        FBR Asset Investment Corporation
                        [Designation of Senior Security]

         FBR Asset Investment Corporation, a Virginia corporation (hereinafter
called the "Corporation," which term shall include any successor corporation
under the Indenture hereinafter referred to), for value received, hereby
promises to pay to , or registered assigns, upon presentation, the principal sum
of DOLLARS on _____________, and to pay interest on the outstanding principal
amount thereon from _____________, or from the most recent Interest Payment Date
to which interest has been paid or duly provided for, semi-annually in arrears
on _______ and _________ in each year, commencing _______________, at the rate
of __% per annum, until the entire principal amount hereof is paid or made
available for payment. The interest so payable, and punctually paid or duly
provided for on any Interest Payment Date will, as provided in the Indenture, be
paid to the Person in whose name this Senior Security (or one or more
Predecessor Senior Securities) is registered at the close of business on the
Regular Record Date for such interest which shall be the ________ or ________
(whether or not a Business Day), as the case may be, next preceding such
Interest Payment Date. Any such interest not so punctually paid or duly provided
for shall forthwith cease to be payable to the Holder on such Regular Record
Date, and may either be paid to the Person in whose name this Senior Security
(or one or more Predecessor Senior Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice whereof shall be given to Holders of Senior
Securities of this series not more than 15 days and not less than 10 days prior
to such Special Record Date, or may be paid at any time in any other lawful
manner not inconsistent with the requirements of any securities exchange on
which the Senior Securities may be listed, and upon such notice as may be
required by such exchange, all as more fully provided in the Indenture. Payment
of the principal of, Make-Whole Amount, if any, on, and interest on this Senior
Security will be made at the office or agency of the Corporation maintained for
that purpose in the City of _____________, State of ________, or elsewhere as
provided in the Indenture, in such coin or currency of the United States of
America as at the time of payment is legal tender for payment of public and
private debts; provided, however, that at the option of the Corporation payment
of interest may be made by (i) check mailed to the address of the Person
entitled thereto as such address shall appear in the Security Register kept for
the Senior Securities pursuant to Section 305 of the Indenture (the "Security
Register") or (ii) transfer to an account of the Person entitled thereto located
inside the United States.

         This Senior Security is one of a duly authorized issue of securities of
the Corporation (herein called the "Senior Securities"), issued and to be issued
in one or more series under an Indenture, dated as of _________, 200_ (herein
called the "Indenture"), between the Corporation and
_____________________________ (herein called the "Trustee," which term includes
any successor trustee under the Indenture with respect to the Senior
Securities), to which Indenture and all indentures supplemental thereto
reference is hereby made for a statement of the
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respective rights, limitations of rights, duties and immunities thereunder of
the Corporation, the Trustee and the Holders of the Senior Securities and of the
terms upon which the Senior Securities are, and are to be, authenticated and
delivered. This Senior Security is one of the series designated as the
"[designation of Senior Securities]," limited in aggregate principal amount to
$_____________.

         The Senior Securities may be redeemed at any time at the option of the
Corporation, in whole or in part, upon notice of not more than 60 nor less than
30 days prior to the Redemption Date, at a redemption price equal to the sum of
(i) the principal amount of the Senior Securities being redeemed plus accrued
interest thereon to the Redemption Date and (ii) the Make-Whole Amount, if any,
with respect to such Senior Securities.

         The following definitions apply with respect to any redemption of the
Senior Securities of this series at the option of the Corporation:

         "Make-Whole Amount" means, in connection with any optional redemption
or accelerated payment of any Senior Security, the excess, if any, of (i) the
aggregate present value as of the date of such redemption or accelerated payment
of each dollar of principal being redeemed or paid and the amount of interest
(exclusive of any interest accrued to the date of redemption or accelerated
payment) that would have been payable in respect of such dollar if such
redemption or accelerated payment had not been made, determined by discounting,
on a semiannual basis, such principal and interest at the Reinvestment Rate
(determined on the third Business Day preceding the date such notice of
redemption is given or declaration of acceleration is made) from the respective
dates on which such principal and interest would have been payable if such
redemption or accelerated payment had not been made, over (ii) the aggregate
principal amount of the Senior Securities being redeemed or paid.

         "Reinvestment Rate" means .25% (one-fourth of one percent) plus the
arithmetic mean of the yields under the respective headings "This Week" and
"Last Week" published in the Statistical Release under the caption "Treasury
Constant Maturities" for the maturity (rounded to the nearest month)
corresponding to the remaining life to maturity, as of the payment date of the
principal being redeemed or paid. If no maturity exactly corresponds to such
maturity, yields for the two published maturities most closely corresponding to
such maturity shall be calculated pursuant to the immediately preceding sentence
and the Reinvestment Rate shall be interpolated or extrapolated from such yields
on a straight-line basis, rounding in each of such relevant periods to the
nearest month. For the purposes of calculating the Reinvestment Rate, the most
recent Statistical Release published prior to the date of determination of the
Make- Whole Amount shall be used.

         "Statistical Release" means the statistical release designated "H.15
(519)" or any successor publication which is published weekly by the Federal
Reserve System and which establishes yields on actively traded United States
government securities adjusted to constant maturities or, if such statistical
release is not published at the time of any determination under the Indenture,
then such

                                       -2-
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other reasonably comparable index which shall be designated by the Corporation.

         The Indenture contains provisions for defeasance at any time of (a) the
entire indebtedness of the Corporation on this Senior Security and (b) certain
restrictive covenants and the related defaults and Events of Default applicable
to the Corporation, in each case, upon compliance by the Corporation with
certain conditions set forth in the Indenture, which provisions apply to this
Senior Security.

         If an Event of Default with respect to the Senior Securities shall
occur and be continuing, the principal of, and the Make-Whole Amount, if any,
on, the Senior Securities may be declared due and payable in the manner and with
the effect provided in the Indenture.

         As provided in and subject to the provisions of the Indenture, the
Holder of this Senior Security shall not have the right to institute any
proceeding with respect to the Indenture or for the appointment of a receiver or
trustee or for any other remedy thereunder, unless such Holder shall have
previously given the Trustee written notice of a continuing Event of Default
with respect to the Senior Securities, the Holders of not less than 25% in
principal amount of the Senior Securities at the time Outstanding shall have
made written request to the Trustee to institute proceedings in respect of such
Event of Default as Trustee and offered the Trustee reasonable indemnity and the
Trustee shall not have received from the Holders of a majority in principal
amount of the Senior Securities at the time Outstanding a direction inconsistent
with such request, and shall have failed to institute any such proceeding, for
60 days after receipt of such notice, request and offer of indemnity. The
foregoing shall not apply to any suit instituted by the Holder of this Senior
Security for the enforcement of any payment of principal hereof or any interest
on or after the respective due dates expressed herein.

         The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Corporation and the rights of the Holders of the Senior Securities under the
Indenture at any time by the Corporation and the Trustee with the consent of the
Holders of not less than a majority in principal amount of the Outstanding
Senior Securities. The Indenture also contains provisions permitting the Holders
of specified percentages in principal amount of the Senior Securities at the
time Outstanding, on behalf of the Holders of all Senior Securities, to waive
compliance by the Corporation with certain provisions of the Indenture and
certain past defaults under the Indenture and their consequences. Any such
consent or waiver by the Holder of this Senior Security shall be conclusive and
binding upon such Holder and upon all future Holders of this Senior Security and
of any Senior Security issued upon the registration of transfer hereof or in
exchange herefor or in lieu hereof, whether or not notation of such consent or
waiver is made upon this Senior Security.

         No reference herein to the Indenture and no provision of this Senior
Security or of the Indenture shall alter or impair the obligation of the
Corporation, which is absolute and unconditional, to pay the principal of,
Make-Whole Amount, if any, on, and interest on this Senior Security at the
times, place and rate, and in the coin or currency, herein prescribed.

                                       -3-
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         As provided in the Indenture and subject to certain limitations therein
set forth, the transfer of this Senior Security is registrable in the Security
Register, upon surrender of this Senior Security for registration of transfer at
the office or agency of the Corporation in any Place of Payment where the
principal of, Make-Whole Amount, if any, on, and interest on this Senior
Security are payable, duly endorsed by, or accompanied by a written instrument
of transfer in form satisfactory to the Corporation and the Security Registrar
for the Senior Securities (the "Security Registrar") duly executed by, the
Holder hereof or his attorney duly authorized in writing, and thereupon one or
more new Senior Securities of this series, of authorized denominations and for
the same aggregate principal amount, will be issued to the designated transferee
or transferees.

         The Senior Securities of this series are issuable only in registered
form without coupons in denominations of $1,000 and any integral multiple
thereof. As provided in the Indenture and subject to certain limitations therein
set forth, Senior Securities of this series are exchangeable for a like
aggregate principal amount of Senior Securities of this series of a different
authorized denomination, as requested by the Holder surrendering the same.

         No service charge shall be made for any such registration of transfer
or exchange, but the Corporation may require payment of a sum sufficient to
cover any tax or other governmental charge payable in connection therewith.

         Prior to due presentment of this Senior Security for registration of
transfer, the Corporation, the Trustee and any agent of the Corporation or the
Trustee may treat the Person in whose name this Senior Security is registered as
the owner hereof for all purposes, whether or not this Senior Security be
overdue, and neither the Corporation, the Trustee nor any such agent shall be
affected by notice to the contrary.

         No recourse under or upon any obligation, covenant or agreement
contained in the Indenture or in this Senior Security, or because of any
indebtedness evidenced thereby, shall be had against any promoter, as such or,
against any past, present or future shareholder, officer or director, as such,
of the Corporation or of any successor, either directly or through the
Corporation or any successor, under any rule of law, statute or constitutional
provision or by the enforcement of any assessment or by any legal or equitable
proceeding or otherwise, all such liability being expressly waived and released
by the acceptance of this Senior Security by the Holder thereof and as part of
the consideration for the issue of the Senior Securities.

         All terms used in this Senior Security which are defined in the
Indenture shall have the meanings assigned to them in the Indenture.

         THE INDENTURE AND THE SENIOR SECURITIES, INCLUDING THIS SENIOR
SECURITY, SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE
COMMONWEALTH OF VIRGINIA.

         Pursuant to a recommendation promulgated by the Committee on Uniform
Security Identification Procedures, the Corporation has caused "CUSIP" numbers
to be printed on the Senior Securities as a convenience to the Holders of the
Senior Securities. No representation is made as to the correctness or accuracy
of such CUSIP numbers as printed on the Senior Securities, and reliance may be
placed only on the other identification numbers printed hereon.

                                       -4-
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         Unless the certificate of authentication hereon has been executed by or
on behalf of the Trustee by manual signature, this Senior Security shall not be
entitled to any benefit under the Indenture or be valid or obligatory for any
purpose.

         IN WITNESS WHEREOF, the Corporation has caused this instrument to be
duly executed under its corporate seal this day of , .

                        FBR Asset Investment Corporation


                        By: ________________________________
                            Name:___________________________
                            Title:__________________________

Attest:


By:_____________________________
   Name:________________________
   Title:_______________________


[SEAL]

TRUSTEE'S CERTIFICATE OF AUTHENTICATION:

         This is one of the Senior Securities of the series designated
"[designation of Senior Securities]" pursuant to the within-mentioned Indenture.

 __________________________,
       as Trustee


By:________________________
   Authorized Signatory

                                       -5-
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--------------------------------------------------------------------------------

                                 ASSIGNMENT FORM

                   FOR VALUE RECEIVED, the undersigned hereby
                        sells, assigns and transfers unto

PLEASE INSERT SOCIAL
SECURITY OR OTHER IDENTIFYING
NUMBER OF ASSIGNEE

_____________________________________________________________


_____________________________________________________________
             (Please Print or Typewrite Name and Address including
                             Zip Code of Assignee)


_____________________________________________________________
the within Senior Security of FBR Asset Investment Corporation and __________
hereby does irrevocably constitute and appoint


_____________________________________________________________
Attorney to transfer said Senior Security on the books of the within-named
Corporation with full power of substitution in the premises.


Dated: _________________________________________

________________________________________________


NOTICE: The signature to this assignment must correspond with the name as it
appears on the first page of the within Senior Security in every particular,
without alteration or enlargement or any change whatever.