The K44 Duo codelock is programmable for up to two doors. This is useful, for example, in situations such as when one wants to use the same keypad to control access both through a garage door and the entrance door located next to the garage door. The doors can either have the same code or different codes. The K44 Duo has a total code capacity of 30 codes, (twenty 4-digit codes and ten 6-digit codes).