Reprogrammable Master code and user code (for guests). * Can program 1 master code and 9 user codes - Pins can have from 1 to 15 digits. * Fits in standard door knob installation hole - Adjustable latch backset 2 3/8" to 2 3/4". * Equip with backup battery power adapter to use when out of battery * Package Include: 1 x Keyless Electronic Digital Door Lock