Serial Number RFID Key Fob 1,ABS material ; 2,water and dust proof 3,different ... color is adapted..... Serial Number RFID Key Fob 1,ABS material ;2,water and dust proof3,different color4 ... S70,Mifare Ultralight ,etc ....... the specification of the TK4100 Key fob Specification of the TK4100Memory64bitSecurity featurePassword needed when read or write ...