【2 TYPES】Rewritable type - can read and rewrite,T5577 chip which compatible with EM4305 chip.Static type - cannot be changed after writing,compatible with TK4100 EM4100 chip. | 【SUPPORT READ WRITE FREQUENCY】Compatible with 125khz RFID reader to gain access. | 【WIDELY APPLICATION】Can be used for elevator card,access control system,Parking card,proximity. | 【ADVANTAGES】No external power required. | 【AFTER SALE GUARANTEE】We care for every customer's feeling. If this product does not meet or exceed your expectations, please contact us at first, we will solve the problem immediately.