1. The lock is already equipped with a MasterCard/keychain and does not require programming or activation. You just need to install 2 AA alkaline batteries to use the lock. 2. This lock is suitable for wooden doors and can also be used for drawers, lockers, cabinets, and sliding doors. There is no need to drill holes, and it will not damage your cabinets. It has rebound and locking functions and is easy to operate. 3. It is compatible with 13.56KHZ IC chip cards. 4. The stainless - steel bolt and ABS plastic lock body are durable and corrosion - resistant. 5. The motor has a service life of around 100,000 times, and the static power consumption is less than 5A. You can set one master card to open all locks, so you only need to keep one key to control all the locks. 6. Specifications: - Type: 3 keychains - Power supply: 4 AA alkaline batteries (not included) - Battery service life: Over 15 months - Operating temperature: -30 degrees Celsius to 80 degrees Celsius - Anti - static performance: Over 15,000V, and information can be saved even in a strong electrostatic environment - Power consumption: Approximately 200mA - Low - voltage alarm: 4.8V - Suitable thickness of cabinet or wardrobe doors: Within 50mm - Color: Black - Material: Stainless steel + ABS - Dimensions: 11.5x8x5.5 cm / 4.53x3.15x2.17 inches 7. Package contents: - 1 lock core (main body) - 1 door buckle (side buckle) - 3 cards - 1 external power supply - 1 installation screw bag (6 screws) 8. Only the above package contents are included, and no other products are included. 9. Note: Light and different displays may cause the color of the item to vary slightly from the actual product. The allowable measurement error is +/- 1 - 3 cm.