berjalan 50Pcs T5577 Writable 125khz RFID Key Fob Proximity ID Card Token Tag, Rewritable

FREQUENCY: 125kHz; Sensing Distance: 2.5 to 10 cm (1 to 4 inch); Data Storage Life: 10 Years. CHIPS: T5577 Chips, it doesn't have pre-programmed id number, so need to write the id on it before you read, so make sure you have the writer before you buy it. WRITABLE & REWRITABLE: It's rewritable chip, and it can write in 125khz id format and H ID WG 125khz format. Suitable for making new and back-up tags. MATERIAL: High-Quality copper coil inside. Casing Material is ABS plastic. Waterproof & . Package includes 50Pcs. NOTE: You cannot add them to RFID locks directly. You must write data into them by a 125kHz RFID card writer before use. They are blank tags, no data inside. Can write by 125KHz RFID writer/copier,CAN NOT WORK WITH ONITY SYSTEM and Proxmark3 RDV4.