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    <ReturnTs>2025-06-02T13:58:12-05:00</ReturnTs>
    <TaxPeriodEndDt>2024-12-31</TaxPeriodEndDt>
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      <PreparerFirmEIN>382706146</PreparerFirmEIN>
      <PreparerFirmName>
        <BusinessNameLine1Txt>YEO &amp; YEO PC</BusinessNameLine1Txt>
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        <AddressLine1Txt>6018 Eastman Ave</AddressLine1Txt>
        <CityNm>Midland</CityNm>
        <StateAbbreviationCd>MI</StateAbbreviationCd>
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    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2024-01-01</TaxPeriodBeginDt>
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        <BusinessNameLine1Txt>Master Insulators Association</BusinessNameLine1Txt>
      </BusinessName>
      <BusinessNameControlTxt>MAST</BusinessNameControlTxt>
      <PhoneNum>9896316140</PhoneNum>
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        <AddressLine1Txt>PO Box 2144</AddressLine1Txt>
        <CityNm>Midland</CityNm>
        <StateAbbreviationCd>MI</StateAbbreviationCd>
        <ZIPCd>48641</ZIPCd>
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    <BusinessOfficerGrp>
      <PersonNm>Robert Williams</PersonNm>
      <PersonTitleTxt>Member</PersonTitleTxt>
      <PhoneNum>9896316140</PhoneNum>
      <SignatureDt>2025-05-20</SignatureDt>
      <DiscussWithPaidPreparerInd>1</DiscussWithPaidPreparerInd>
    </BusinessOfficerGrp>
    <IRSResponsiblePrtyInfoCurrInd>1</IRSResponsiblePrtyInfoCurrInd>
    <PreparerPersonGrp>
      <PreparerPersonNm>Tara L Stensrud</PreparerPersonNm>
      <PTIN>P01284969</PTIN>
      <PhoneNum>9896316060</PhoneNum>
      <PreparationDt>2025-05-20</PreparationDt>
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    <TaxYr>2024</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
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      <TotalExpensesAmt>40931</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>39437</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>49135</NetAssetsOrFundBalancesBOYAmt>
      <OtherChangesInNetAssetsAmt>0</OtherChangesInNetAssetsAmt>
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      <InfoInScheduleOPartIIIInd>X</InfoInScheduleOPartIIIInd>
      <PrimaryExemptPurposeTxt>Resolving problems and issues of the Insulation Industry</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>To provide an instrument through which members of the Heatand Frost Insulation Industry may coordinate their effortsin handling common problems. The association has meetingsof its members and directors to determine various problemsaffecting the industry.</DescriptionProgramSrvcAccomTxt>
        <GrantsAndAllocationsAmt>0</GrantsAndAllocationsAmt>
        <ProgramServiceExpensesAmt>0</ProgramServiceExpensesAmt>
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      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm>Robert Williams</PersonNm>
        <TitleTxt>President</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>1.00</AverageHrsPerWkDevotedToPosRt>
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        <PersonNm>Robert Williams</PersonNm>
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          <CityNm>Midland</CityNm>
          <StateAbbreviationCd>MI</StateAbbreviationCd>
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      <ForeignOfficeInd>0</ForeignOfficeInd>
      <DonorAdvisedFndsInd>0</DonorAdvisedFndsInd>
      <OperateHospitalInd>0</OperateHospitalInd>
      <TanningServicesProvidedInd>0</TanningServicesProvidedInd>
      <RelatedOrganizationCtrlEntInd>0</RelatedOrganizationCtrlEntInd>
      <PoliticalCampaignActyInd>0</PoliticalCampaignActyInd>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Form 990-EZ, Part I, Line 16 - Other Expenses</FormAndLineReferenceDesc>
        <ExplanationTxt>Description: Accounting. Amount: 625. Description: Training. Amount: 24,775. Description: Insurance. Amount: 387. Description: Fees. Amount: 20. Description: Dues. Amount: 1,818. Description: Member services. Amount: 13,306. Total to Form 990-EZ, line 16: 40,931.</ExplanationTxt>
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      <DeclarationDesc>The organization did not, during the year, receive any funds, directly,or indirectly, to pay premiums on a personal benefit contract.The organization, did not, during the year, pay any premiums, directly,or indirectly, on a personal benefit contract.</DeclarationDesc>
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