LibsTag100LibsTag100 for Books and Magazines, Size 50x50 mm (2x2 in), White Paper Face. Ideal for most Library Applications Standards: ISO 18000 3, ISO 15693 Frequency: HF 13. 56 MHz User Memory: 1024 bit (32 blocks) Read Write Cycle: 100,000 IC & Inlay: NXP ICode SLIX with aluminium antenna Data Retention: Guaranteed for the lifetime of the library item under standard conditions (20C 68F and 50% relative humidity) Storage Conditions: Temperature: 15C to 50C