Features: brand new and high quality 1000M Ethernet interface to realize high-speed networking of equipment. Because of the modulars form, PI4B and CM4 have high modularity, which is convenient for users to use DIY.PI4B+CB1, with high cost performance, can become a low-cost choice for 3D printer users who use ordinary motherboards to run Klipper. Dual Micro HDMI-compatibles interface, external HDMI-compatibles screen, high-definition sound quality, high-definition picture quality output. Micro-SD interface, can insert SD card. PI4B with CB1 installed, the performance can be close to 3B, and can also be used instead of 3B. PI4B: The PI4B uses the same card holder as the CM4, and can be directly mounted to the PI4B board-to-board. In addition, the PI4B uses the same board frame and interface as the 4B, so the PI4B with the CM4 installed can be used as a 4B. Specifications: CB1: CB1 is a computing core board similar to CM4. CPU: Allwinner H616, Quad-core Cortex-A53 @1.5GHz. GPU: Mali G31MP2, support OpenGL3.2. RAM: 512MB/1GB DDR3L SDRAM. Display: HDMI2.0A interface, support 4K display. USB 2.0 port. 100M Ethernet + 100M WiFi. The same header as the CM4. Package Includes: 1 x BIGTREETECHPI4B Adapter 1 x CB1 Core Board note: 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!