Handheld shape design, comfortable grip . 2 buttons for simple operations. Standalone operation, no need to connect to computer or PC, easy to use. Built-in individual LED lights and buzzer indicator. Reading distance is 0 - 6cm. Can only copy 125KHz RFID card. Compatible with T5577, 5200, EM4305, EN4305. Parameter: Read: 125KHz ID (EM4100, TK4100, etc.) cards or keys Write: 5200, EM4305, T5577, 8310, 8268, etc. cards or keys Built-in: individual LED lights, buzzer indicator, transceiver antenna Power Supply: 3V (2 x AAA battery), not included. Batteries can be purchased separately. Durability: Read / Write up to 20,000 times Note: Tested before shipment. If the device does not read a card, the card may be of an unsupported type. If the device does not write to a card, the card may be of an unsupported type or non-writable type. These conditions are not caused by the device. Due to different production batches, there may be variations in product appearance, color, and printed text. These differences do not affect functionality. Type: 1 Keyfob Color: Blue Material: Plastic Package Contents: 1 x RFID Card Reader Kit Note: Light reflection and differences in display screens may cause slight color variations between the image and the actual item. Measurement error allowed is +/- 1-3 cm.