TagsForDroid NFC Key Chain (MIFARE 1K)
Package contents: 1 NFC Key ChainNFC Chip Specifications:NFC Chip Type: MIFARE(TM) classic compatibleMemory Size: 1024bytes (1KB)Rewrite Endurance: 100,000 cyclesLockable: yes (can be made read only)Data Retention: 10 yearsOperating Frequency: 13.56 MHzOperating Range < 2cm (depends on device)Compatibility:  compatible with NFC enabled smartphones (read FAQ for more info)drop in replacement for Samsung TectilesKeychain:Material: Rigid dark gray plasticDimensions:  36mm x 6mmCompatibility: These tags are Mifare Classic 1k (similar to Samsung Tectiles). Due to technical limitations on the Galxy S4, Nexus 4 phone and Nexus 10 tablet, these tags will not work on those devices. They will work perfectly on the Samsung Galaxy S3 and other NFC enabled Android phones. If you are not sure, please consult your phone manufacturer.