10 PCS Writable 125kHz RFID Blank Card Proximity ID Card Key Token Tag Rewritable T5577 Universal * Note: They are blank RFID cards, no data inside. You need to write data into them to use. * Frequency: 125kHz; Sensing Distance: 1 to 4 inch (2.5 to 10 cm); Storage Capacity: 330 bits. Data Storage Life: 10 Years. * Writable & Rewritable. It can be erased and written 100,000 times. Suitable for making new and back-up cards, with the 125kHz RFID card writer/copier. * Chip: ATMEL T5577 (compatible with other universal 125kHz cards/tags). * Card Size: 3.38" x 2.18" (same size as a credit card). Casing Material: PVC Plastic. * Package includes 10 PCS.