Power of Attorney for Robert Wunar

This filing is an Exhibit 24, a Power of Attorney, for Robert Wunar, Chief Operating Officer of Ultra Clean Holdings, Inc. (UCTT). Wunar grants power of attorney to Sheri Savage, Paul Y. Cho, Marty Estkowski, and Katarina Uhrinova. These attorneys-in-fact are authorized to execute and file SEC forms 3, 4, and 5 on Wunar's behalf, as required by Section 16 of the Securities Exchange Act of 1934. They can perform all necessary actions related to these filings, including making decisions on the form and content of the documents. This power of attorney remains in effect until Wunar is no longer required to file these forms, or until it is revoked in writing. The filing is dated March 12, 2026.