No backlight, keeps displaying last content for a long time even when power down. Ultra low power consumption, basically power is only required for refreshing. SPI interface, for connecting with controller boards like /for /Nucleo, etc. Onboard voltage translator, compatible with 3.3V/5V MCUs. Operating voltage: 3.3V/5V Interface: 3-wire SPI, 4-wire SPI Outline dimension: 89.5mm X 38mm Display size: 66.89mm X 29.05mm Dot pitch: 0.138 X 0.138 Resolution: 296 X 128 Display color: black, white Grey level: 2 Partial refresh time: 0.3s Full refresh time: 2s Refresh power: 26.4mW(typ.) Standby power: less than 0.017mW Viewing angle: more than 170 degree Colour: blue Material: plastic Package Contents: 1 * 2.9 Inch E-Paper Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.