Exhibit 4.1


POLYPORE INTERNATIONAL,
INC.,


and


THE BANK OF NEW YORK, as
Trustee


 


 






 


FIRST SUPPLEMENTAL
INDENTURE


Dated as of July 3, 2007


TO


INDENTURE


Dated as of October 18,
2004






 


101/2% Senior Discount Notes due 2012






 


 











FIRST SUPPLEMENTAL INDENTURE dated as of July 3, 2007
(this “Supplemental Indenture”), to the Indenture dated as of October 18, 2004
(the “Indenture”) between Polypore International, Inc., a Delaware corporation
(the “Company”) and The Bank of New York, a New York banking corporation, as
trustee (the “Trustee”).


W I T N E S S E T
H


WHEREAS, the Company and the Trustee have heretofore
executed and delivered the Indenture, and the Company has issued pursuant to
the Indenture its 101⁄2% Senior Discount Notes due 2012 (the “Notes”);


WHEREAS, Section 9.02 of the Indenture provides that
the Company and the Trustee may, with the consent of the Holders (as defined in
the Indenture) of at least a majority in Accreted Value (as defined in the
Indenture) of the Notes then outstanding voting as a single class (including
consents obtained in connection with a tender offer or exchange for, or
purchase of, the Notes), amend or supplement the Indenture, subject to certain
limitations set forth in the Indenture;


WHEREAS, the Company has solicited the consents of the
Holders of the Notes pursuant to the Offer to Purchase and Consent Solicitation
Statement dated June 15, 2007 (as the same may be amended or supplemented from
time to time, the “Statement”), and in the related Letter of Transmittal and
Consent dated June 15, 2007 (as the same may be amended or supplemented from
time to time, together with the Statement, the “Offer”), to the proposed
amendments to the Indenture upon the terms and conditions set forth therein
(the “Amendments”);


WHEREAS, the Company has received and delivered or
caused to be delivered to the Trustee the consents of the Holders of at least a
majority in Accreted Value of the outstanding Notes to the Amendments pursuant
to the Offer;


WHEREAS, the Company has been authorized by resolution
of its board of directors to enter into this Supplemental Indenture;


WHEREAS, the Company has requested that the Trustee
join in the execution and delivery of this Supplemental Indenture;


WHEREAS, all other acts and proceedings required by
law, by the Indenture and by the articles of incorporation and bylaws of the
Company to make this Supplemental Indenture a valid and binding agreement for
the purposes expressed herein, in accordance with its terms, have been duly
done and performed; and


WHEREAS, the Amendments contained herein will become
operative (the “Operative Date”) upon the Company’s acceptance for payment of
at least a majority in Accreted Value of the outstanding Notes that are validly
tendered and not withdrawn on or prior to the consent date contemplated by the
Offer.


NOW, THEREFORE, in consideration of the premises and
the covenants and agreements contained herein, and for other good and valuable
consideration the receipt of which is hereby acknowledged, the Company and the
Trustee hereby agree as follows:











ARTICLE 1


SECTION 1.01. Definitions.


Capitalized terms used in this Supplemental Indenture
and not otherwise defined herein shall have the meanings assigned to such terms
in the Indenture.


ARTICLE 2


SECTION 2.01. Amendments to Table of Contents.


(a)                                  The
Table of Contents of the Indenture is amended by deleting the titles to Section
3.09, Sections 4.02 through 4.04 and Sections 4.06 through 4.16 and inserting,
in each case, in lieu thereof the phrase “[intentionally omitted]”.


(b)                                 The
Table of Contents of the Indenture is amended by re-titling Section 5.02 “Successor
Person Substituted”.


ARTICLE 3


SECTION 3.01. Elimination of Certain
Definitions in Article 1 of the Indenture.


Sections
1.01 and 1.02 of the Indenture are amended by deleting all definitions of
terms, and references to definitions of terms, that are used exclusively in the
text of the Indenture and the Notes that are being otherwise eliminated by this
Supplemental Indenture.


SECTION 3.02. Elimination of Certain
Provisions in Article 3 of the Indenture.


Section 3.09 of the Indenture is amended by deleting the text of such
Section in its entirety and inserting in lieu thereof the phrase “[intentionally
omitted]”.


SECTION 3.03. Elimination of Certain
Provisions in Article 4 of the Indenture.


(a)                                  Section
4.02 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(b)                                 Section
4.03 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(c)                                  Section
4.04 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.











(d)                                 Section
4.06 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(e)                                  Section
4.07 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(f)                                    Section
4.08 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(g)                                 Section
4.09 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(h)                                 Section
4.10 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(i)                                     Section
4.11 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(j)                                     Section
4.12 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(k)                                  Section
4.13 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(l)                                     Section
4.14 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(m)                               Section
4.15 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


(n)                                 Section
4.16 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the phrase “[intentionally omitted]”.


SECTION 3.04. Amendment of Certain Provisions
in Article 5 of the Indenture.


(a)                                  Section
5.01 of the Indenture is amended by deleting the text of such Section in its
entirety and inserting in lieu thereof the following:


“The Company shall not, in a single transaction or
series of related transactions, consolidate or merge with or into any Person,
or sell, assign, transfer, lease, convey or otherwise dispose of all or
substantially all of the Company’s assets to any Person unless (i) either: (a)
the Company shall be the surviving or continuing corporation or limited
liability company; or (b) the Person (if other than the Company) formed by such
consolidation or into which the Company is merged or the Person which acquires
by sale, assignment, transfer, lease, conveyance or other disposition the
properties and assets of the Company substantially as an entirety: (x) shall be
a corporation or limited liability company organized and validly existing under
the laws of the United States of America or any State thereof or the District
of Columbia; and (y) shall expressly assume, by supplemental indenture (in form
and substance satisfactory to the Trustee), executed 











and delivered to the
Trustee, the due and punctual payment of the principal of, premium, if any, and
interest on all of the Notes and the performance of every covenant and all
obligations of the Company under the Notes, this Indenture and the Registration
Rights Agreement to be performed or observed on the part of the Company and
(ii) the Company or the Surviving Entity shall have delivered to the Trustee an
Officers’ Certificate and an Opinion of Counsel, each stating that such
consolidation, merger, sale, assignment, transfer, lease, conveyance or other
disposition and, if a supplemental indenture is required in connection with
such transaction, such supplemental indenture comply with the applicable
provisions of this Indenture and that all conditions precedent in this
Indenture relating to such transaction have been satisfied.


For purposes of the foregoing, the transfer (by lease,
assignment, sale or otherwise, in a single transaction or series of
transactions) of all or substantially all of the properties or assets of one or
more Subsidiaries of the Company the Capital Stock of which constitutes all or
substantially all of the properties and assets of the Company, shall be deemed
to be the transfer of all or substantially all of the properties and assets of
the Company.  However, transfer of assets
from Foreign Subsidiaries to the Company or a domestic Subsidiary of the
Company will not be subject to this Section 5.01.”


(b)                                 Section
5.02 of the Indenture is amended by re-titling the Section “Successor Person
Substituted”.


SECTION
3.05. Elimination of Certain Provisions in Article 6 of the Indenture.


Section 6.01 of the Indenture is amended by:


(a)                                  deleting
the text of clauses (c) through (g) in their entirety and inserting in lieu
thereof the phrase “[intentionally omitted]”; and


(b)                                 deleting
the reference in clause (b) to “(including the failure to make a payment to
purchase Notes tendered pursuant to a Change of Control Offer or a Net Proceeds
Offer on the date specified for such payment in the applicable offer to
purchase)”.


ARTICLE 4


SECTION 4.01. Elimination of Certain Provisions
in Article 8 of the Indenture.


Section 8.04(b) of the Indenture is amended by
deleting the text of such Section in its entirety and inserting in lieu thereof
the phrase “[intentionally omitted]”.


ARTICLE 5


SECTION 5.01. Effectiveness of Amendments to
Indenture.


This Supplemental Indenture shall be effective upon
its signing by the parties hereto and the Amendments shall not be operative
until the Operative Date.











SECTION 5.02. Continuing Effect of Indenture.


Except as expressly provided herein, all of the terms,
provisions and conditions of the Indenture and the Notes shall remain in full
force and effect.


SECTION
5.03. Construction of Supplemental Indenture.


This Supplemental Indenture is executed as and shall
constitute an indenture supplemental to the Indenture and shall be construed in
connection with and as part of the Indenture for all purposes, and every Holder
of Notes heretofore or hereafter authenticated and delivered under the
Indenture shall be bound by the Indenture as amended by this Supplemental
Indenture.  THE LAWS OF THE STATE OF NEW
YORK SHALL GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE.


SECTION 5.04. Trust Indenture Act Controls.


If any provision of this Supplemental Indenture
limits, qualifies or conflicts with another provision that is required to be
included in this Supplemental Indenture or the Indenture by the Trust Indenture
Act of 1939, as amended, as in force at the date that this Supplemental
Indenture is executed, the provisions required by said Act shall control.


SECTION 5.05. Trustee Disclaimer.


The recitals contained in this Supplemental Indenture
shall be taken as the statements of the Company and the Trustee assumes no
responsibility for their correctness. 
The Trustee makes no representations as to the validity or sufficiency
of this Supplemental Indenture


SECTION 5.06. Notices.


The following addresses are the updated notice
addresses to be used for any notice or communication by the Company or the
Trustee to the other party:


If to the Company:


Polypore, Inc.

11430 North Community House Road, Suite 350

Charlotte, NC  28277

Facsimile No.: (704) 587-8409

Attention: Lynn K. Amos


With copies to:


Willkie Farr & Gallagher LLP

787 Seventh Avenue

New York, NY 10019

Facsimile No.: (212) 728-8214

Attention: Cristopher Greer, Esq.











If to the Trustee:


The Bank of New York

101 Barclay Street, Fl 4 East

New York, New York 10286

Facsimile No.: (212) 815-5802 

Attention:  Global Trust Services


SECTION
5.07. Counterparts.


The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy (including facsimile copies) shall be
an original, but all of them together represent the same agreement.


SECTION 5.08. Severability.


In case any provision in this Supplemental Indenture
shall be invalid, illegal or unenforceable, the validity, legality and
enforceability of the remaining provisions shall not in any way be affected.











IN WITNESS WHEREOF, the parties have caused this
Supplemental Indenture to be duly executed as of the date first written above.


	
  

  	
  POLYPORE
  INTERNATIONAL, INC.

  	 

	
   

  	
   

  	 

	
   

  	
   

  	 

	
   

  	
  By

  	
   

  
	
   

  	
   

  	
  Name: Robert B.
  Toth

  	 

	
   

  	
   

  	
  Title: President
  and Chief Executive Officer

  	 

	
   

  	
   

  	 

	
   

  	
   

  	 

	
   

  	
  THE BANK OF NEW
  YORK,

  	 

	
   

  	
  as Trustee,

  	 

	
   

  	
   

  	 

	
   

  	
   

  	 

	
   

  	
  By

  	
   

  	 

	
   

  	
   

  	
  Name:

  	 

	
   

  	
   

  	
  Title:

  	 




 


[Supplemental Indenture]