The CM4 interface protection board Designed based on for CM4.Note: Not include for Raspberry CM4. Onboard standard CM4 connector, supports access to Compute Module 4 Lite / eMMC series motherboards and corresponding baseboards or expansion boards. [Note] In testing, the probability of CM4 damage is greatly reduced by using this adapter board. If used with the Heatsink, the probability of damage to the adapter board will also be reduced. The function of the board is to physically replace the damage of the CM4 socket. In testing, most of the damage is caused by frequent plugging and unplugging of the CM4 socket. Different batches may have different appearances, which will not affect the use; different light or display may cause color difference in the actual product the color of the mounting accessories is random,don't accept the specified color Colour:Blue+Black Material:PCB+Aluminum alloy Package Contents: 1x CM4 Protection Board 1x heat sink with mounting 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.