Features: This is Near Field Communication driver module for 1.54inch electronic ink screen, with resolution of 200x200. Support wireless transmission of Picture information through Near Field Communication enabled card readers or mobile phones, and display the information through electronic ink screen. Not contain batteries or other power sources and is suitable for application environment with limited power supply. The displayed content can be customized and controlled by users at any time through their smartphones, making it convenient and flexible. Suitable as equipment labels, shelf labels, information storage, etc. Suitable for mobile phone key hanging accessories, business cards, decorations and other applications. Specifications: Material: Aluminum, PC Color: silver white Size: approx. 11x9x2cm/4.33x3.54x0.79inch Power supply method: Near Field Communication Power Supply Resolution: 200x200 Point distance: 0.138x0.138 Refreshing time: 8-second Viewing angle:>170° Package Includes: 1Pc 1.54inch Screen Near Field Communication Driver Module note: No battery, no positioning function, no access card, no bus card function, the product is only a driver module which use Near Field Communication function to change three color ink screen of the picture. For software downloads, please contact customer service for consultation. Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.