【RFID chip】Using the original T5577 chip with a frequency of 125kHz, it can easily replicate TK4100 (EM4100) and EM4305 smart cards. 【 Ring Material 】It is made by dropping epoxy resin onto the shell of zirconia ceramics, which will not make people feel too bulky and thick visually and tactile. You can take it to shower and wash your hands. 【 Ring Size 】Sizes determined according to American standards: 6 #, 7 #, 8 #, 9 #, 10 #, 11 #, 12 #. Allowing you more choices without worrying about not having a ring that fits your size. 【 Usage Scenario 】ID smart cards with a frequency of 125kHz, such as TK4100 (EM4100) and EM4305, can be rewritten and replicated. 【 Product Advantages 】The ring made of zirconia all ceramic will not be damaged even when dropped at a height of 1 meter. It is waterproof, not easy to stick dust, and can be wiped clean with a clean cloth. You can wear it for outdoor activities such as running, swimming, etc.