The can be used to unlock doors, mobile phones, transfer information. Through the NFC radio frequency communication technology and mobile phone connection to the mobile phone function operation and sharing of . Smart ring by touching the phone NFC signal area, to achieve the screen to unlock, application lock, quick start application, send read business , information and other functions. It is a great choice for your loved ones. Features - Color: Black. - Material: Stainless Steel. - Size: Approx. 2.31 x 2.31 x 0.8cm/ 0.9 x 0.9 x 0.3 inch (LxWxH). - Through the NFC radio frequency communication technology and mobile phone connection to the mobile phone function operation and sharing of . - Smart ring by touching the phone NFC signal area, to achieve the screen to unlock; application lock; quick start application; send read business , information and other functions. - Multi-functional NFC smart ring, the main function is to store and exchange personal information, as well as mobile content and personal encryption unlock, support for , , , millet and other DNF-enabled mobile phone. - Quickly start the phone application, in advance will need to quickly start the program startup written in the smart ring, when the smart ring the phone will automatically and start the program. - Touch unlock, hand wear ring touch unlocks, screen lock, application lock set (some phones need to ROOT, can use the function). - Lock / unlock the program, select the application you want to lock/unlock, write the smart ring, only the ring touch the phone to start the application, to protect personal . - Touch the sharing / personal memorandum, you can store private content in the ring, you can also share the phone business , wifi password, graphic , can also be used as a private memo to unlock the only way to unlock. - No / waterproof, built-in ultra- DNF chip, no electricity to work, easy to wear. Package list: 3 x 8mm Smart Ring Wearable Smart Rings Digital Ring for Phone with Functions