RD-J electronic code lock as a stand alone use for all kinds of door in residential, apartment, building office etc.Dimension: 230x167x142mmPatent No.: ZL 003 09335.2 Main Features.1) Novel and noble appearance2) Simple installation; open by code3) Use standby key to open lock for emergency occasions,4) when in low power supply, supply(6V DC) to the power jack to activate the lock.5) 10 groups of code from 1 up to 13 digits available.6) Single or double code functions for anti-theft protection7) Alert for wrong code insert8) Up-to-date material for stable and durable performance Technical Parameter:1. Suitable for door thickness : 35~50mm2. Power supply: 4 LR6 (AM3, AA)1.5V alkaline batteries3. Service life of battery: approx. 20,000times4. It will alarm for low power supply, and still can open for approx. 50 times.