Exhibit31.1

CERTIFICATION

I, O. Joe Caldarelli,certify that:

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| 1.  | I have reviewed this quarterlyreport on Form 10-Q of CPI International,Inc; |

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| 2.  | Based on my knowledge, this quarterlyreport does not contain any untrue statement of a material fact or omitto state a material fact necessary to make the statements made, inlight of the circumstances under which such statements were made, notmisleading with respect to the period covered by this quarterlyreport; |

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| 3.  | Based on my knowledge, the financialstatements, and other financial information included in this quarterlyreport, fairly present in all material respects the financialcondition, results of operations and cash flows of the registrant asof, and for, the periods presented in this quarterly report; |

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| 4.  | The registrant's other certifying officer andI are responsible for establishing and maintaining disclosure controlsand procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) for the registrant andhave: |

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|  | a)  | Designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to bedesigned under our supervision, to ensure that material informationrelating to the registrant, including its consolidated subsidiaries, ismade known to us by others within those entities, particularly duringthe period in which this quarterly report is beingprepared; |

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|  | b)  | Evaluated the effectiveness of theregistrant's disclosure controls and procedures and presented inthis report our conclusions about the effectiveness of the disclosurecontrols and procedures, as of the end of the period covered by thisquarterly report based on such evaluation;and |

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|  | c)  | Disclosed in this report any change in theregistrant’s internal control over financial reporting thatoccurred during the registrant’s most recent fiscal quarter thathas materially affected, or is reasonably likely to materially affect,the registrant’s internal control over financial reporting;and |

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| 5.  | The registrant's other certifyingofficer and I have disclosed, based on our most recent evaluation ofinternal control over financial reporting, to the registrant'sauditors and the audit committee of registrant's board ofdirectors (or persons performing the equivalentfunctions): |

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|  | a)  | All significant deficiencies andmaterial weaknesses in the design or operation of internal control overfinancial reporting which are reasonably likely to adversely affect theregistrant's ability to record, process, summarize and reportfinancial information; and |

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|  | b)  | Any fraud, whetheror not material, that involves management or other employees who have asignificant role in the registrant’s internal control overfinancialreporting. |

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| Date:February  13,2006 |  | Signature: |  | /s/   O. JoeCaldarelli                                              |
|                   |  |       |  | O.Joe Caldarelli, Chief ExecutiveOfficer                                                                                                                                                                                                                                                                            |
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