for Robin Nano V3.1 is an upgraded version of Robin , with the MCU changed from STM32F407VGT6 to STM32F407VET6. More importantly, Robin NanoV3.1 has improved its anti-interference performance, such as adding Schottky diodes in temperature measurement circuits and MOS circuits, and adding protection at the power input terminal. Similar to Robin Nano V2.0, the firmware of MKS Robin Nano V3.1 is also based on 2. X. In fact, WIFI module adds SPI connection,SPI speed is much higher than serial communication (currently released firmware still only supports serial communication, and the SPI communication version be updated soon) Support dual Z-,Parallel to the Z- motor interface, dual Z-axes can also be used when using dual extruders Hign-concerned Chemical:None Model Number:MKS Robin nano V3.1 Item Type:Motherboard Colour:As Shown Material:PCB Package Contents: 1 * Motherboard 1 pack * accessories Only the above package content, other products are not included. Note: Light reflection 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.