Features: High performance 32-bit 64 MHz ARM Cortex-M0+ series STM32G0B1VET6 MCU Onboard BOOT button to enable DFU mode- to update the bootloader. The thermistor circuit is protected to prevent MCU damage from shorted heated bed and heater cartridge connection. Four 2-pin fan ports, one always-on fan port, and two 4-pin fan ports. All fans can realize VIN12V, 5V-voltage selection via jumpers-, and different voltages can be set separately for different ports. Integrated SPI- and UART mode- of TMC- driver and DIAG- pin, easily configurable with jumpers-. Supports power loss recovery, filament- runout sensor, auto power-off, BLTouch-, proximity switch, RGB, etc.Onboard CAN bus port.Onboard UART and I2C expansion output ports. The SPI- expansion port is +3.3V and +5V selectable, which is convenient to connect expansion modules, such as an ADXL345 accelerometer. Specifications: Item：SKRat V1.0 3D Printer Motherboard MCU: 32-bit 64 MHz ARM Cortex-M0+ series STM32G0B1VET6 Onboard CAN Bus ADXL345 PT100 Support ADXL345 VIN12V/5V With: 7 Fan Ports Compatible：RatOS 2.0 For Klipper 3D Printer Control Board Size：approx11x8.5cm/4.33x3.35in Package Includes: 1 PC SKRat V1.0 32bit 3D Control Board note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!