Existing key blades, electronics, batteries, and transponder chips are reused (not included with purchase) and packaged into the new case, with no reprogramming. Re-cutting a key is not necessary, however, the OEM case must be destroyed to extract the key, as the key is molded into it. In most cases, the key will pull out easily, though in some instances it must be cut out. If it is desired to retain the original case/key, an additional OEM shell/key only may be purchased and that key can be cut. Alternatively, the integrated key blade may be discarded altogether and a separate key can be used. This method requires the use of the OEM valet key or the purchase of a Toyota key with the H chip (Toyota P/N 89785-0D170), this key must be cut and reprogrammed at the dealer or locksmith. In some cases the transponder is easily removed, though in most cases it will be glued and require cutting the case and/or heat for removal, this can be somewhat difficult. If care is not used during removal, the transponder may become damaged and stop working (the fob/key will not start the vehicle). AJT Design is not responsible for broken transponders.