Compliant with Bluetooth 4.0 BLE standard Supports intelligent door lock app for opening doors Built-in clock chip Built-in antenna Built-in passive switch (relay) Note: 1. Below the minimum operating voltage, it may cause the module to malfunction. Exceeding the maximum operating voltage may cause module damage 2. Generally, modules are in a sleep state and only switch to other states when unlocking with the app 3. Extreme environments can cause modules to malfunction Note: Factory batches are different. Slight differences in appearance do not affect functionality Color: Green Material: Plastic Size: 38x27mm (excluding wires) Package Contents: 1 x Electronic Lock Module Only the above package content, other products are not included Note: Light reflection and different displays may cause the color of the item in the picture to differ slightly from the actual item. Measurement allowed error is +/- 1-3cm