and accessory products installed in connection to such insulation materials— (A) placed in service in connection with a mechanical system which— (i) is located in the United States, and (ii) is of a character subject to an allowance for depreciation, and (B) which result in a reduction in energy loss from the mechanical system which is greater than the expected reduction from the installation of insulation materials which meet the minimum requirements of Reference Standard 90.1 (as defined in section 179D(c)(2)). (c) Termination This section shall not apply to mechanical insulation labor costs paid or incurred after December 31, 2025. . (b) Credit allowed as part of general business credit Section 38(b), as amended by the preceding provisions of this Act, is further amended by striking plus at the end of paragraph (33), by striking the period at the end of paragraph (34) and inserting , plus , and by adding at the end the following new paragraph: (35) the mechanical insulation labor costs credit determined under section 45V(a). . (c) Conforming amendments (1) Section 280C is amended by adding at the end the following new subsection: (i) Mechanical insulation labor costs credit (1) In general No deduction shall be allowed for that portion of the mechanical insulation labor costs (as defined in section 45V(b)) otherwise allowable as deduction for the taxable year which is equal to the amount of the credit determined for such taxable year under section 45V(a). (2) Similar rule where taxpayer capitalizes rather than deducts expenses If— (A) the amount of the credit determined for the taxable year under section 45V(a), exceeds (B) the amount allowable as a deduction for such taxable year for mechanical insulation labor costs (determined without regard to paragraph (1)), the amount chargeable to a capital account for the taxable year for such costs shall be reduced by the amount of such excess. . (2) The table of sections for subpart D of part IV of subchapter A of chapter 1, as amended by the preceding provisions of