1. PI4B uses the same card holder as CM4, which can be directly installed to PI4B board-to-board. In addition, PI4B uses the same board and interface as for 4B, so PI4B with CM4 installed can be used as 4B.2. 1000M Ethernet interface to realize high-speed networking of equipment3. Dual --compatible interface, external -compatible screen, high-definition sound quality, high-definition quality output4. -sd interface, can insert SD card5. 4 USB2.0 ports are reserved for USB ports, which can be connected to the mouse and keyboard.Product name: PI4B expansion boardDisplay: 2*-compatible 2.0A interface, support 4K displayUSB: 4*USB 2.0 portsNetwork port: 1*1000M Ethernet interfaceOthers: CSI, interface. Easy connection of cameras and monitorsBack: 1*-sd interfacePower input: Type-C 50.25VSupported module types: for CB series, each version for CM4 moduleProduct size: 85x56mmColour:blackMaterial:PCB+MetalPackage Contents:1 x PI4B expansion boardOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.