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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No. )*
MTS Systems Corporation
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(Name of Issuer)
Common Stock
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(Title of Class of Securities)
553777103
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(CUSIP Number)
12-31-99
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(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:
/X/ Rule 13d-1(b)
/ / Rule 13d-1(c)
/ / Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting
person's initial filing on this form with respect to the subject class of
securities, and for any subsequent amendment containing information which would
alter the disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934 ("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however, see
the Notes).
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CUSIP No. 553777103
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Mairs and Power Growth Fund, Inc.
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(1) Names of Reporting Persons.
I.R.S. Identification Nos. of above person (entities only).
41-6019924
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(2) Check the Appropriate Box if a Member (a) / /
of a Group (See Instructions) (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
St. Paul, Minnesota USA
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Number of (5) Sole Voting Power
Shares
Beneficially 1,248,100
Owned by ---------------------------------------------------
Each Reporting
Person With: (6) Shared Voting Power
N/A
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(7) Sole Dispositive Power
1,248,100
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(8) Shared Dispositive Power
N/A
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,248,100
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(10) Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See
Instructions) / /
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(11) Percent of Class Represented by Amount in Row (9)
6.0%
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(12) Type of Reporting Person (See Instructions)
IV
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ITEM 1.
(a) Name of Issuer
MTS Systems Corporation
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(b) Address of Issuer's Principal Executive Offices
14000 Technology Drive, Eden Prairie, MN 55344-2290
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ITEM 2.
(a) Name of Person Filing
Mairs and Power Growth Fund, Inc.
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(b) Address of Principal Business Office or, if none, Residence 332
Minnesota Street, W-1420 First National Bank Bldg., St. Paul, MN 55101
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(c) Citizenship
USA
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(d) Title of Class of Securities
Common Stock
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(e) CUSIP Number
553777103
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ITEM 3. IF THIS STATEMENT IS FILED PURSUANT TO SECTIONS 240, 13D-1 (b) OR 240,
13d-2 (b) OR (c), CHECK WHETHER THE PERSON FILING IS A:
(a) / / Broker or dealer registered under section 15 of the Act (15
U.S.C. 78c).
(b) / / Bank as defined in section 3(a)(6) of the Act (15 U.S.C.
78c).
(c) / / Insurance company as defined in section 3(a)(19) of the Act
(15 U.S.C. 78c).
(d) /X/ Investment company registered under section 8 of the
Investment Company Act of 1940 (15 U.S.C. 80a-8).
(e) / / An investment adviser in accordance with section 240.
13d-1(b)(1)(ii)(E).
(f) / / An employee benefit plan or endowment fund in accordance
with section 240. 13d-1(b)(1)(ii)(F).
(g) / / A parent holding company or control person in accordance
with section 240. 13d-1(b)(1)(ii)(G).
(h) / / A savings association as defined in section 3(b) of the
Federal Deposit Insurance Act (12 U.S.C. 1813).
(i) / / A church plan that is excluded from the definition of an
investment company under section 3(c)(14) of the Investment
Company Act of 1940 (15 U.S.C. 80a-3).
(j) / / Group, in accordance with section 240, 13d-1(b)(1)(ii)(J).
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ITEM 4. OWNERSHIP
Provide the following information regarding the aggregate number and
percentage of the class of securities of the issuer identified in Item 1.
(a) Amount beneficially owned:
1,248,100 shares
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(b) Percent of class:
6.0%
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(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote
1,248,100
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(ii) Shared power to vote or to direct the vote
N/A
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(iii) Sole power to dispose or to direct the disposition of
1,248,100
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(iv) Shared power to dispose or to direct the disposition of
N/A
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ITEM 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
If this statement is being filed to report the fact that as of the date
hereof the reporting person has ceased to be the beneficial owner of more than
five percent of the class of securities, check the following. / /
ITEM 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
N/A
ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY
N/A
ITEM 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
N/A
ITEM 9. NOTICE OF DISSOLUTION OF GROUP
N/A
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ITEM 10. CERTIFICATION
By signing below I certify that, to the best of my
knowledge and belief, the securities referred to above
were acquired and are held in the ordinary course of
business and were not acquired and are not held for the
purpose of or with the effect of changing or influencing
the control of the issuer of the securities and were not
acquired and are not held in connection with or as a
participant in any transaction having that purpose or
effect.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.
February 3, 2000
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Date
/s/ George A. Mairs, III
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Signature
George A. Mairs, III/President
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Name/Title
