Item Type: ID Card Lock Material: Stainless Steel Product Size: Approx. 13 x 10 x 4cm / 5.1 x 3.9 x 1.6in Battery Specification: Button Battery Battery Model: Cr2025l Battery Capacity: 140mah Lock Battery Type: AA Alkaline Dry Battery (Shipped Without Battery) Lock Battery Model: Aa Number of Lock Batteries: 4 Package List 3 x Lock Body 1 x Remote Control 1 x Intelligent Management Card 3 x Key 2 x Id Sensing Card 1 x Lock Core 1 x Screw Pack 1Double Head Lock: The door needs to swipe a card or mechanical key to unlock, go out must swipe a card or mechanical key to unlock, high security. 2Silent Unlocking: The battery lock uses a silent motor, and the operation of unlocking the lock is quieter and noiseless, won't disturb family or neighbors. 3Wiring Free Design: The lock needs simple installation, no wiring trouble, with mounting screw package, fast installation, no professional technology is required. 4Anti Theft Function: Swiping ID card and battery wiring is a integrated design, enhance security, protect your property safety, with a high anti theft performance. 5Wide Range of Applications: Wiring free lock can be installed to home, can be opened in two ways, by swiping a card or using a key,very convenient.