MAGNA-LAB INC.

July 27, 2000

Itzhak Goldenberg
Noga Investments in Technologies, Ltd.
Netanya, Israel

Allen Perres
RKP Capital Partner, LLC
154 West Hubbard Street, Sixth Floor
Chicago, Illinois  60610

         Re:  Magna-Lab Inc.

Dear Gentlemen:

Reference is made to that certain letter agreement dated December 17, 1999 (the
"December 17 Letter"), as amended by letters dated March 7, 2000 (the "March 7
Letter") and May 26, 2000 (the "May 26 Letter") (collectively, the "Noga Letter
Agreement") between Magna-Lab Inc. (the "Company") and Noga Investments in
Technologies, Ltd. (successor in interest to Noga Electrotechnica Limited)
("Noga"). Reference is also made to that certain letter agreement dated December
6, 1999, as amended by letter dated December 20, 1999, (the "Perres Letter
Agreement") between the Company and Allen Perres.

Pursuant to the Noga Letter Agreement, Noga paid a non-refundable deposit of
$250,000 and purchased a total of $500,000 worth of the Company's common stock
at $0.22 per share and agreed to purchase an additional $2,250,000 worth of the
Company's common stock at $0.22 per share by May 27, 2000. Noga paid an
additional non-refundable deposit of $100,000 to permit Noga to extend its time
to pay the balance of its commitment to July 27, 2000. Noga has requested that
in exchange for additional investment undertakings by Noga as described herein,
that it be granted additional time to pay the balance of its existing
commitment.

The Noga Letter Agreement is hereby amended as follows:

1.       Paragraph 4 of the December 17 Letter is deleted in its entirety and
         replaced with the following:

      "By July 28, 2000, Noga will purchase an additional $750,000 worth of
      common stock of Magna-Lab at $0.22 per share. By September 15, 2000, Noga
      will purchase an additional $700,000 worth of common stock of Magna-Lab at
      $0.22 per share. By October 15, 2000, Noga will purchase an additional
      $700,000 worth of common stock of Magna-Lab at $0.22 per share. Noga has
      the right to make partial payments prior to payment dates set forth above
      for a

<PAGE>

      pro rata number of shares. Notwithstanding anything in this paragraph 4 to
      the contrary, in the event that for any 5 consecutive trading days or any
      10 trading days in a 30 trading day period, the bid price of Magna-Lab's
      common stock closes at $2.00 or more per share at any time after the date
      of this and prior to October 15, 2000, Magna-Lab shall thereafter have the
      right to demand, by delivery of written notice to Noga, that Noga pay such
      $2,150,000 amount immediately. Within 15 days of delivery of such notice,
      Noga shall pay to Magna-Lab such amount".

The foregoing payment terms will be reflected in a promissory note delivered by
Noga to the Company promptly following execution of this letter agreement.

2.     All non-refundable deposits paid by Noga to the Company will be applied
       toward the balance of Noga's commitment only if such balance is timely
       paid.

3.     Paragraph 5 of the Noga Letter Agreement is deleted in its entirety and
       replaced with the following:

      "Noga hereby irrevocably commits to purchase 13,636,363 shares of Class A
      Common Stock of Magna-Lab for $3,000,000, or $0.22 per share, payable as
      follows: $1,000,000 by September 30, 2000 and the balance by October 31,
      2000. The payment terms will be reflected in a promissory note delivered
      by Noga to Magna-Lab promptly following execution of the letter agreement
      dated July 25, 2000. Magna-Lab shall issue and deliver the shares in
      installments as and when payment is received.

Effective upon final payment of the full $2,150,000 referred to in paragraph 1
above, Noga agrees to exercise options to purchase 3,500,000 shares of the
Company's Class A Common Stock at $0.02 per share which represents all of the
options to which Noga is entitled pursuant to the Noga Letter Agreement. Noga
shall deliver the $70,000 exercise price at the same time as the exercise of
such options, together with such other documentation as the Company or its
counsel deem necessary or appropriate in connection with such option exercise.

Additionally, Perres elects to exercise options to purchase 3,500,000 shares of
the Company's Class A Common Stock at $0.02 per share which represents all of
the options to which Perres is entitled pursuant to the Perres Letter Agreement.
Perres shall deliver $70,000 to the Company within 10 days of the date hereof as
full payment for the exercise of such options, together with such other
documentation as the Company or its counsel deem necessary or appropriate in
connection with such option exercise.

The Company will use its best efforts to obtain approval from its stockholders
to increase its authorized shares in an amount sufficient to cover the share
issuances contemplated by this letter agreement, as well as such additional
number shares as the Board determines to be appropriate.


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<PAGE>

By this letter, Perres agrees to make an additional investment in the Company.
Perres agrees to purchase 9,090,909 shares of Class A Common Stock of the
Company for $2,000,000 or $0.22 per share. Perres shall pay such amount to the
Company by September 30, 2000. The payment terms will be reflected in a
promissory note delivered by Perres to the Company promptly following execution
of this letter agreement. The Company shall issue and deliver the shares after
it has timely received payment therefor. It is understood that although Perres
is hereby irrevocably committing to purchase such shares, it is contemplated
that the Company will first offer investors in the recent private placement as
well as members of management an opportunity to purchase such shares on the same
basis.

Subject to timely receipt by the Company of the above-referenced $3,000,000 from
Noga and $2,000,000 from Perres, Magna agrees to seek a listing of its common
stock on either Nasdaq or Amex at such time as it reasonably believes it will be
able to meet the applicable minimum listing requirements.

This letter agreement shall be governed by and construed in accordance with the
laws of the State of New York (without giving effect to its rules as to
conflicts of law). This letter agreement may be executed in counterparts, each
of which will be deemed an original, but all of which taken together will
constitute one and the same instrument.

If this letter accurately reflects your understanding of the matters discussed
herein, please execute the copy of this letter in the space provided below and
return the executed copy to us to indicate your agreement.

Very truly yours,

MAGNA-LAB INC.


By:   /s/ Lawrence A Minkoff
      -------------------------------------------------
      Name:  Lawrence A. Minkoff
      Title: President

Agreed to and accepted this __ day of July, 2000


NOGA INVESTMENTS IN TECHNOLOGIES LTD.
(with respect to the paragraphs applicable to it)


By:  /s/ Itzhak Goldenberg
     --------------------------------------------------
     Name:   Itzhak Goldenberg
     Title   General Manager

Agreed to and accepted this _27th day of July, 2000 (with respect to the
paragraphs applicable to him)


/s/   Allen Perres
-------------------------------------------------------
Allen Perres


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