Exhibit 4.1

FIRST AMENDMENT TO  CREDIT AND GUARANTY AGREEMENT

ThisFIRST AMENDMENT TO CREDIT AND GUARANTY AGREEMENT(this
"Amendment"), dated as of March 25, 2005, is amongMEDICAL DEVICE MANUFACTURING, INC., a
Colorado corporation ("Company"),ACCELLENT INC.(formerly UTI Corporation), a Maryland
corporation ("Holdings"), certain Subsidiaries of Company party hereto, andCREDIT SUISSE FIRST BOSTON, acting through its
Cayman Islands Branch, as administrative agent (in such capacity, "Administrative Agent").

RECITALS

WHEREAS,Company, Holdings, the Guarantor Subsidiaries party thereto, the Lenders party thereto, Administrative
Agent and Credit Suisse First Boston, acting through its Cayman Islands Branch, as sole lead arranger and sole book runner, have entered into the Credit and Guaranty Agreement dated as of
June 30, 2004 (the "Credit Agreement");

WHEREAS,Company, Holdings and the Guarantor Subsidiaries desire to provide for certain amendments to the Credit Agreement specified
herein; and

WHEREAS,the Requisite Lenders and Administrative Agent have agreed to amend the Credit Agreement as provided herein upon the terms and
subject to the conditions set forth herein.

NOW, THEREFORE,in consideration of the premises made hereunder, and for good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto, intending to be legally bound, hereby agree as follows:

Section 1.Definitions. Unless otherwise expressly defined herein, all capitalized terms used herein and defined in the Credit
Agreement shall be used herein as so defined.

Section 2.Amendments to Section 1.1.



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Section 3. Amendment to Section 2.1.Section 2.1of the Credit
Agreement is hereby deleted and replaced in its entirety with the following:

"2.1 Tranche C Term Loans



Section 4.Amendment to Section 2.4(a).Section 2.4(a)of the Credit
Agreement is hereby amended by deleting the last sentence thereof.

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Section 5. Amendment to Section 2.4(e).Section 2.4(e)of the Credit
Agreement is hereby amended by deleting the first sentence thereof and replacing such sentence with the following:



Section 6.Amendment to Section 2.6.Section 2.6of the Credit
Agreement is hereby amended by inserting the following sentence immediately following the first sentence of suchSection 2.6:

"The
proceeds of the Tranche C Term Loans made on the Closing Date shall be applied by Company to repay Existing Term Loans in full on the First Amendment Effective Date."

Section 7. Amendment to Section 2.7(c).Section 2.7(c)of the Credit
Agreement is hereby amended by replacing the reference to "Tranche B Term Loan" contained therein and with a reference to "Tranche C Term Loan".

Section 8.Amendment to Section 2.8(a).Section 2.8(a)of the Credit
Agreement is hereby amended by deleting clause (iii) contained therein and replacing such clause with the following:



Section 9.Amendment to Section 2.8(b).The first sentence of Section 2.8(b)of the Credit Agreement is hereby deleted and replaced in its entirety with the
following:



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Section 10.Amendment to Section 2.12.Section 2.12of the Credit
Agreement is hereby deleted and replaced in its entirety with the following:

"The
principal amounts of the Tranche C Term Loans shall be repaid in consecutive quarterly installments (each, an "Installment") in the
aggregate amounts set forth below on the last day of each calendar quarter (each, an "Installment Date"), commencing March 31, 2005:

Installment Date

InstallmentMarch 31, 2005

$
485,000.00June 30, 2005

$
485,000.00September 30, 2005

$
485,000.00December 31, 2005

$
485,000.00March 31, 2006

$
485,000.00June 30, 2006

$
485,000.00September 30, 2006

$
485,000.00December 31, 2006

$
485,000.00March 31, 2007

$
485,000.00June 30, 2007

$
485,000.00September 30, 2007

$
485,000.00December 31, 2007

$
485,000.00March 31, 2008

$
485,000.00June 30, 2008

$
485,000.00September 30, 2008

$
485,000.00December 31, 2008

$
485,000.00March 31, 2009

$
485,000.00June 30, 2009

$
485,000.00Tranche C Term Loan Maturity Date

$
184,300,000.00


Notwithstanding
the foregoing, (x) such Installments shall be reduced in connection with any voluntary or mandatory prepayments of the Tranche C Term Loans in accordance with Sections 2.13,2.14and2.15, as applicable; and
(y) the Tranche C Term Loans, together with all other amounts owed hereunder with respect thereto, shall, in any event, be paid in full no later than the Tranche C Term Loan Maturity Date."

Section 11.Amendments to Section 2.13.



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Section 12.Amendments to Section 2.16.



Section 13.Amendment to Section 2.23.Section 2.23of the Credit
Agreement is hereby amended by replacing clause (A) contained therein with the following:

"(A)
an amount equal to the principal of, and all accrued interest and premium (if any) on, all outstanding Loans of the Terminated Lender,"



Section 15.Addition of Section 5.16. The following newSection 5.16to the Credit Agreement is hereby added to the Credit Agreement immediately followingSection 5.15thereof:



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Section 16.Amendment to Section 6.7.Section 6.7of the Credit
Agreement is hereby amended by deleting clause (l) thereof and replacing such clause with the following:



Section 17.Amendment to Section 10.6.Section 10.6(c)of the Credit
Agreement is hereby amended by replacing the reference to "Tranche B Term Loan" contained in clause (ii) thereof with a reference to "Tranche C Term Loan".

Section 18. Deletion of Schedule 1.1.Schedule 1.1to the Credit
Agreement is hereby deleted.

Section 19.Replacement of Appendix and Exhibit.Appendix A-1andExhibit B-1to the Credit Agreement are hereby deleted and replaced with Appendix A-1andExhibit B-1attached hereto.

Section 20. Extension of Time Period for German Subsidiary Stock Pledge. Notwithstanding Section 4.4.1(b)of the Pledge and Security Agreement, it is hereby agreed that the Credit Parties shall not be required to deliver evidence of
the pledge under German law of 65% of the equity interests in UTISFM Feinmechanik GmbH, a German limited liability company, until the date that is the earlier of (A) the second anniversary of
the Closing Date and (B) 60 days after a determination by the Credit Parties not to actively pursue the sale of UTISFM Feinmechanik GmbH or substantially all its assets.

Section 21. Conditions Precedent. This Amendment shall become effective on the date upon which Administrative Agent shall have
received: (i) this Amendment, executed by Company, Holdings and each Guarantor Subsidiary; (ii) executed Lender Consents, substantially in the form attached hereto as Annex I("Lender Consents"), from the Requisite Lenders; (iii) executed copies of the favorable
written opinions of each of Hogan & Hartson LLP, counsel for Credit Parties, and such other local counsel for Credit Parties as Administrative Agent may reasonably request, in each case
covering such matters as Administrative Agent may reasonably request, in form and substance reasonably satisfactory to Administrative Agent (and each Credit Party hereby instructs such counsel to
deliver such opinions to Administrative Agent and Lenders); (iv) a notice of prepayment pursuant toSection 2.13of the Credit Agreement,
regarding the prepayment in full of the Existing Term Loans on the First Amendment Effective Date; (v) payment of all reasonable expenses of Administrative Agent for which invoices have

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been
presented (including the invoices of Skadden, Arps, Slate, Meagher & Flom LLP); and (vi) such other documents, agreements, UCC financing statements, resolutions, certificates and
information as Administrative Agent shall reasonably request.

Section 22. Representations and Warranties. Company hereby represents and warrants to Administrative Agent and the Lenders that, as
of the date hereof and after giving effect to this Amendment:



Section 23.Confirmation; Security Interests. Each of the undersigned Credit Parties hereby acknowledges that it has reviewed the
terms and provisions of this Amendment and consents to the amendments and modifications to the Credit Agreement effected thereby. Each of the undersigned Credit Parties hereby (a) confirms and
continues the pledge and security interest in the Collateral granted by it pursuant to the Pledge and Security Agreement, (b) acknowledges and agrees that the pledge and security interest in
the Collateral granted by it pursuant to the Pledge and Security Agreement shall be in favor of the Collateral Agent and shall continue to secure the Secured Obligations, including but not limited to
the Tranche C Term Loans, (c) pledges and grants to the Collateral Agent, for the benefit of the Secured Parties, a lien on and security interest in and to all of the right, title and interest
of such Grantor in, to and under the Collateral to secure the payment and performance in full of all the Secured Obligations and (d) except in the case of Company, confirms and agrees that it
is bound by the Credit Agreement as a guarantor thereunder, by virtue of its having been an original signatory thereto, a successor to such an original signatory or a signatory to a supplement
thereto. The Pledge and Security Agreement and the other Collateral Documents are and shall continue to be in full force and effect and are hereby in all respects ratified and confirmed by each of the
undersigned Credit Parties. Without limiting the generality of the foregoing, the Collateral

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Documents
and all of the Collateral described therein do and shall continue to secure the payment of all Secured Obligations under and as defined therein. Each of the undersigned Credit Parties hereby
further agrees that (i) the Tranche C Term Loans made to the Company by the applicable Lenders and all Obligations owing to such Lenders shall be subject to and shall benefit from all of the
provisions of the Credit Agreement, including without limitation Section 7 thereunder, and the other Credit Documents applicable to the Tranche C Term Loans and the other Loans, and
(ii) the Lenders providing Tranche C Term Loans are "Secured Parties" under the Pledge and Security Agreement.

Section 24.Reference to Agreement. Each of the Credit Documents, including the Credit Agreement, and any and all other agreements,
documents or instruments now or hereafter executed and/or delivered pursuant to the terms hereof or pursuant to the terms of the Credit Agreement as amended hereby, are hereby amended so that any
reference in such Credit Documents to the Credit Agreement, whether direct or indirect, shall mean a reference to the Credit Agreement as amended hereby. This Amendment shall constitute a Credit
Document under the Credit Agreement.

Section 25.Costs and Expenses. Company shall pay on demand all reasonable costs and expenses of Administrative Agent (including
the reasonable fees, costs and expenses of counsel to Administrative Agent) incurred in connection with the preparation, execution and delivery of this Amendment.

Section 26.Governing Law.THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HEREUNDER SHALL BE
GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

Section 27.Execution. This Amendment may be executed in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed shall be deemed to
be an original and all of which taken together shall constitute one and the same agreement. Delivery of an executed counterpart of a signature page to this Amendment by telecopier shall be effective
as delivery of a manually executed counterpart of this Amendment.

Section 28. Severability. Any provision of this Amendment held to be invalid, illegal, ineffective or unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity, illegality, ineffectiveness or unenforceability without affecting the validity, legality, effectiveness
and enforceability of the remaining provisions hereof; and the invalidity of a particular provision in a particular jurisdiction shall not invalidate such provision in any other jurisdiction.

Section 29.Limited Effect. This Amendment relates only to the specific matters expressly covered herein, shall not be considered
to be a waiver of any rights or remedies any Lender may have under the Credit Agreement or under any other Credit Document, and shall not be considered to create a course of dealing or to otherwise
obligate in any respect any Lender to execute similar or other amendments under the same or similar or other circumstances in the future. Except as expressly amended hereby, the Credit Agreement shall
remain in full force and effect, and is hereby ratified and confirmed.

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by their respective officers thereunto duly authorized,
as of the date first above written.

| |  | MEDICAL DEVICE MANUFACTURING, INC.,a Colorado corporation
| |  | ---------------------------------------------------------
| |  | By:                                                      
| |  |                                                          
| |  | Name:                                                    
| |  | Title:                                                   
| |  | ACCELLENT INC.,a Maryland corporation                    
| |  | By:                                                      
| |  |                                                          
| |  | Name:                                                    
| |  | Title:                                                   

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| |  | AMERICAN TECHNICAL MOLDING, INC.,a California corporation BRIMFIELD ACQUISITION CORP.,a Delaware corporation BRIMFIELD PRECISION, LLC,a Delaware limited liability company CYCAM, INC.,a Pennsylvania corporation ELX, INC.,a Pennsylvania corporation G&D, INC.,a Colorado corporation HAYDEN PRECISION INDUSTRIES, LLC,a Delaware limited liability company KELCO ACQUISITION, LLC,a Delaware limited liability company MEDSOURCE TECHNOLOGIES, INC.,a Delaware corporation MEDSOURCE TECHNOLOGIES, LLC,a Delaware limited liability company MEDSOURCE TECHNOLOGIES NEWTON, INC.,a Delaware corporation MEDSOURCE TECHNOLOGIES PITTSBURGH, INC.,a Delaware corporation MEDSOURCE TRENTON, INC.,a Delaware corporation MICRO-GUIDE, INC.,a California corporation NATIONAL WIRE & STAMPING, INC.,a Colorado corporation NOBLE-MET, LTD.,a Virginia corporation PORTLYN, LLC,a Delaware limited liability company SPECTRUM MANUFACTURING, INC.,a Nevada corporation TENAX, LLC,a Delaware limited liability company TEXCEL, INC.,a Massachusetts corporation THERMAT ACQUISITION CORP.,a Delaware corporation UTI CORPORATION,a Pennsylvania corporation UTI HOLDING COMPANY,a Delaware corporation VENUSA, LTD.,a New York corporation
| |  | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
| |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
| |  | Name:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
| |  | Title:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
| |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        

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| |  | CREDIT SUISSE FIRST BOSTON,
acting through its Cayman Islands Branch,as Administrative Agent
| |  | --------------------------------------------------------------------------------------------
| |  | By:                                                                                         
| |  |                                                                                             
| |  | Name:                                                                                       
| |  | Title:                                                                                      
| |  | By:                                                                                         
| |  |                                                                                             
| |  | Name:                                                                                       
| |  | Title:                                                                                      

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Annex I

LENDER CONSENT

March    , 2005

Reference
is made to that certain Credit and Guaranty Agreement, dated as of June 30, 2004, among Medical Device Manufacturing, Inc., Accellent Inc. (formerly UTI
Corporation), the Guarantor Subsidiaries party thereto, the Lenders party thereto, and Credit Suisse First Boston, acting through its Cayman Islands Branch, as administrative agent, collateral agent,
sole lead arranger and sole book runner (the "Credit Agreement"; the terms defined therein being used herein as therein defined).

The
undersigned, as a Lender, hereby consents to the First Amendment to Credit and Guaranty Agreement (the "Amendment") in the form
delivered to the undersigned Lender on or prior to the date hereof.

Pursuant
to Section 10.5 of the Credit Agreement, the undersigned Lender hereby (i) consents to the execution by Credit Suisse First Boston, acting through its Cayman
Islands Branch, as Administrative Agent, of the Amendment, and, (ii) if the undersigned Lender holds any Existing Term Loans, elects to convert all of the outstanding principal amount of the
Existing Term Loans held by such undersigned Lender into Tranche C Term Loans.

| |  |                 
| |  | ----------------
| |  | (Name of Lender)
| |  | By:             
| |  |                 
| |  |                 
| |  |                 

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APPENDIX A-1

APPENDIX A-1
TO CREDIT AND GUARANTY AGREEMENT

Tranche C Term Loan Commitments    [on file with Administrative Agent]

|Lender |  | Tranche C
Term Loan Commitment |                | Pro Rata Share |       
|------ |  | ------------------------------ | -------------- | -------------- | ------
|       |  | $                              |                |                |       
|       |  | $                              |                |                |       
|       |  | $                              |                |                |       
|       |  | $                              |                |                |       
|       |  |                                |                |                |       
|Total  |  | $                              | 193,030,000.00 |                | 100.00
|       |  |                                |                |                |       

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EXHIBIT B-1

EXHIBIT B-1 TO
CREDIT AND GUARANTY AGREEMENT

TRANCHE C TERM LOAN NOTE

$[1][    ,    ,]
[2][mm/dd/yy]

FOR VALUE RECEIVED,MEDICAL DEVICE MANUFACTURING, INC., a Colorado corporation
("Company"), promises to pay[NAME OF LENDER]("Payee") or its registered assigns the principal amount of
[1][DOLLARS]($[1][    ,    ,    ])
in the installments referred to below.

Company
also promises to pay interest on the unpaid principal amount hereof, from the date hereof until paid in full, at the rates and at the times which shall be determined in
accordance with the provisions of that certain Credit and Guaranty Agreement, dated as of June 30, 2004 (as it may be amended, restated, amended and restated, supplemented or otherwise
modified, the "Credit Agreement"; the terms defined therein and not otherwise defined herein being used herein as therein defined), by and among
Company,ACCELLENT INC.(formerly UTI Corporation), certain Subsidiaries of Company, as Guarantors, the Lenders party thereto from time to time, CREDIT SUISSE FIRST BOSTON,
acting through its Cayman Islands Branch, as Lead Arranger, Administrative Agent and Collateral Agent, WACHOVIA BANK, NATIONAL ASSOCIATION, as Syndication Agent, andANTARES CAPITAL CORPORATIONand NATIONAL CITY BANK, as Co-Documentation Agents.

Company
shall make principal payments on this Note as set forth in Section 2.12 of the Credit Agreement.

This
Note is one of the "Tranche C Term Loan Notes" in the aggregate principal amount of $193,030,000.00 and is issued pursuant to and entitled to the benefits of the Credit Agreement,
to which reference is hereby made for a more complete statement of the terms and conditions under which the Tranche C Term Loan evidenced hereby was made and is to be repaid.

All
payments of principal and interest in respect of this Note shall be made in lawful money of the United States of America in same day funds at the Principal Office of Administrative
Agent or at such other place as shall be designated in writing for such purpose in accordance with the terms of the Credit Agreement. Unless and until an Assignment Agreement effecting the assignment
or transfer of the obligations evidenced hereby shall have been accepted by Administrative Agent and recorded in the Register, Company, each Agent and Lenders shall be entitled to deem and treat Payee
as the owner and holder of this Note and the obligations evidenced hereby. Payee hereby agrees, by its acceptance hereof, that before disposing of this Note or any part hereof it will make a notation
hereon of all principal payments previously made hereunder and of the date to which interest hereon has been paid; provided, the failure to make a notation of any payment made on this Note shall not
limit or otherwise affect the obligations of Company hereunder with respect to payments of principal of or interest on this Note.

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This
Note is subject to mandatory prepayment and to prepayment at the option of Company, each as provided in the Credit Agreement.

THIS
NOTE AND THE RIGHTS AND OBLIGATIONS OF COMPANY AND PAYEE HEREUNDER SHALL BE GOVERNED BY, AND SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

Upon
the occurrence of an Event of Default, the unpaid balance of the principal amount of this Note, together with all accrued and unpaid interest thereon, may become, or may be declared
to be, due and payable in the manner, upon the conditions and with the effect provided in the Credit Agreement.

The
terms of this Note are subject to amendment only in the manner provided in the Credit Agreement.

No
reference herein to the Credit Agreement and no provision of this Note or the Credit Agreement shall alter or impair the obligations of Company, which are absolute and unconditional,
to pay the principal of and interest on this Note at the place, at the respective times, and in the currency herein prescribed.

Company
promises to pay all costs and expenses, including reasonable attorneys' fees, all as provided in the Credit Agreement, incurred in the collection and enforcement of this Note.
Company and any endorsers of this Note hereby consent to renewals and extensions of time at or after the maturity hereof, without notice, and hereby waive diligence, presentment, protest, demand
notice of every kind and, to the full extent permitted by law, the right to plead any statute of limitations as a defense to any demand hereunder.

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IN WITNESS WHEREOF, Company has caused this Note to be duly executed and delivered by its officer thereunto duly authorized as of the date
and at the place first written above.

| |  | MEDICAL DEVICE MANUFACTURING, INC.
| |  | ----------------------------------
| |  | By:                               
| |  |                                   
| |  |                                   
| |  |                                   

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