Designed to boost the performance of select Synology NAS systems, the M2D18 Dual M.2 SSD Adapter Card from Synology is a PCIe 2.0 x8 expansion card with two M.2 slots exclusively for SSD read/write caching, which will reduce random I/O latency and benefit applications such as photo indexing, file search, and virtualization environments. The M2D18 supports both NVMe and SATA SSDs with form factors of 2280, 2260, and 2242. To help keep things running cool, an attachable heatsink accelerates thermal dissipation and ensure system stability with strong performance. Its integrated bracket will accommodate low-profile and full-height slots. When used with a compatible NAS, users who want to take advantage of SSD caching will no longer need to use a standard storage bay or bays for caching purposes. For example, a 5-bay array with three 10TB hard drives that has two bays set aside for caching will only have 20TB available as a RAID 5. Installing the M2D18 will allow all five bays to be used for storage, meaning that your NAS will have a greater overall capacity. When configured as a RAID 5 with a 10TB drive in each of the five drive bays, you’ll have 40TB available.