Through the NFC radio frequency communication technology and mobile phone connection to the mobile phone function operation and sharing of data. Instructions for use: 1. First, check if your smartphone has NFC function. It can usually be found in the system settings. If no relevant options are found, contact with the manufacturer post-sale support, or search on Google if the smartphone model has NFC function and confirm its NFC area. 2. If your smartphone has NFC function, turn on the NFC switch, search your app for the software which apply NFC, download and install them. 3. Start the NFC APP, perform actions according to the instructions. 4. Since NFC is a near field communication technology, make sure to place the top side of the ring chip right close to the NFC area when reading any data to avoid the failure in reading and writing. Specification: Material: Metal Size: about 4*5*0.5cm/1.57*1.97*0.2in Product Name: NFC Multi-function Smart Ring Size: 6/7/8/9/10/11/12/13 inch Package List: 1 * Smart Ring