Model LH-NFCWYBQ290-1A Color Black/White Size 112*45*4.5mm Battery No Display Size 2.9' Comm Frequency 13.56Mhz Display Refresh time 3 Seconds Comm Standard ISO 14443-A-3 Reader ACR1252U/ACR1251U/USC-8A NFC Wireless E ink tag NFC battery less e ink tag is a new technology with e ink panel which can display contents and images without power or charging,there are many advantages of this products