When sourcing ATM safe locks, prioritize high-security electronic or mechanical combination locks that meet UL 768 (Group 1 or 2) or EN 1300 (Class A, B, or C) standards. Key features should include One-Time Code (OTC) functionality for technician access, audit trail capabilities (storing at least 500+ events), and dual-mode authentication (requiring two users to open). Ensure the lock body is made of heavy-duty zinc alloy or steel with a standard mounting footprint for universal compatibility with major ATM brands like NCR, Diebold, or Wincor.