The Argon ONE M.2 expansion board extends support for SATA M.2 SSDs to maximize the actual potential speeds of your Raspberry Pi 4. Now you can boot through a SATA M.2 SSD for faster boot time and higher storage capacity compared to traditional microSD card. To use it, you just need to replace the bottom of the argon with the expansion board, and the case can now use SSD. Using Raspberry Pi 4 cases is recommended due to the USB 3.0 ports provided by the boards. Argon ONE M.2 supports UASP for Raspberry Pi 4, which means that you can maximize the transfer speeds of your SATA M.2 drive. It is compatible with any M.2 SATA SSD with Key-B and Key B & M. (not for NVME) colour: black Material: aluminum alloy The lower left corner is the product batch number, different batches have different numbers Package Contents: 4 x M.2 expansion board 4 x USB 3.0 adapter 16 x non-slip gaskets 16 x screws