KeylessOption Replacement Key Remote Keyless Emergency Insert Uncut Blade Blank With Transponder Chip for Smart Prox Replacement emergency key that slides into the bottom of smart/prox keys, transponder chip installed inside This key needs to be cut prior to using. No programming is required! Replaces CWTWBU735, CWTWBU624, KR55WK49622, CWTWBU619, KR55WK48903, CWTWBU618,KBRTN001 This is a replacement part to match the original in form and function