PCIe 4.0 Compliant: Supports even the fastest PCIe 4.0 SSDs but also works with older and newer generation SSDs at up to 4.0 speeds. Works in older 3.0/2.0 systems that have PCIe bifurcation support. Compatible with NVMe SSDs in the M.2 2230/2242/2260/2280 form factors for your convenience. Built Cool: Designed with quality aluminum for physical stability and top-notch cooling. Thermal padding is included to ensure the best cooling interface for your SSDs. Optional active cooling (fan) via a rear-positioned switch for high-performance environments. Your drives wont throttle in here. More Storage: Add up to four high-performance NVMe SSDs to a system with a single adapter in a physical x16 PCIe slot with the Quad NVMe SSD to PCIe 4.0 x16 Card (EC-P4BF). The system requires the PCIe bifurcation (lane splitting) function to add more than one SSD with the full 16 lanes required for 3 or 4 drives.