•Multifunctional RFID Ring: The JAKCOM R4 is a versatile RFID wireless radio frequency ring featuring built-in IC and ID modules to replace access cards, parking cards, membership cards, and other wireless RF cards •NFC Integration: With an integrated NFC module, the R4 offers unique cloud services, including virtual call alerts, location notifications, business card sharing, and note-sharing •Simplify Access Control: Conveniently replace traditional access cards with the R4 Smart Ring's IC and ID modules, enhancing security and ease of access •Enhanced Connectivity: The NFC capabilities of the R4 enable seamless interaction with various smart devices and services, making it a versatile tool for modern lifestyles •Stylish and Functional: Not only does the JAKCOM R4 offer cutting-edge technology, but it also boasts a sleek and stylish design, making it a fashionable accessory for everyday wear Regarding Size Measurement: •Use a non-elastic thread to wrap around your finger snugly. •Slightly tighten the thread; otherwise, the ring size may be too large. •Straighten the thread, measure the length, and choose the size based on the table below: Standard US Sizes - Size 8: 57mm, Size 9: 60mm, Size 10: 62.8mm, Size 11: 66mm, Size 12: 70mm. Specifications: Standard US Sizes (Optional) 8 : 57mm 9 : 60mm 10 : 62.8mm 11 : 66mm 12 : 70mm Carrier Frequency 13.56MHz, 125KHz RFID Range 1~3cm IC Module Type UID ID Module Type T5577 NFC Module Type Ntag213 Protection Rating IP68 Operating Temperature -50℃ to +80℃ Compatible Systems iOS, Android Compatible Platforms iOS, Android Materials Ceramic + Metal Diameter About 2.5cm Powered No Need Package included: •1 x Smart Ring •1 x English and Chinese Manual •Other items not included