Power of Attorney Filing for Core & Main, Inc. Director

This filing documents a Power of Attorney granted by M. Susan Hardwick, a Director of Core & Main, Inc. (CNM), to Mikael Olson, Robyn Bradbury, Jackie Burkhardt, and John Stephens. The attorneys-in-fact are authorized to execute and file Section 16 forms (Forms 3, 4, and 5) and Form 144 filings related to the undersigned's securities transactions with the Company. This includes managing EDGAR Next account access and filings with the SEC and stock exchanges. The Power of Attorney remains in effect until Hardwick is no longer required to make such filings and revokes any prior powers of attorney. The filing is dated March 24, 2026, with the signature date of April 2, 2026.