LSDA heavy-duty padlocks are designed to meet special security needs. Our "key-to-match" series padlocks are designed to be compatible with keys that open door locks. The convenience of carrying one key, or the need to include padlocks in a master-key system or a restricted keyway system call for these padlocks. Available Keyways: Arrow (900), Corbin 60 (400), Kwikset KW1 (200), Russwin D1-D4 (1000), Sargent LA-LC (700), Schlage C-K (3000), Schlage C (300), Weiser/Falcon (800), Yale 8 (100)