Hy-Ko 18GM104 Key Blank, Brass, 4.37 in L x 1.87 in W DimensionsContains a computer chip in the head of the key programmed to the vehicle's security system. The ChipKey blank is first electronically programmed with Hy Ko's C3 I tool and then cut on a standard key cutting machine. Duplicate keys requires programming the matching code in order to operate the vehicle. Waterproof. Unit: EA UPC: 029069730635 Model Number: 18GM104