Features: brand new and high quality 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. 1000M Ethernet interface to realize high-speed networking of equipment. Dual Micro HDMI-com interface, external HDMI-com screen, high-definition sound quality, high-definition picture quality outputMicroSD interface, can insert SD card. PI4B with CB1 installed, the performance can be close to 3B, and can also be used instead of 3B. Because of the modulars form, PI4B and CM4 have high modularity, which is convenient for users to use DIY. Specifications: Material: PCB Size: approx. 8.5x5.6cm/3.35x2.20in Package Includes: 1 x BIGTREETECHPI4B Adapter 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!