4 x 18 TB Enterprise-class Storage Solution Yottamaster 4 bay hard drive caddy supports 4 hard drives with a maximum capacity of 72 TB and 18 TB for single disk. For 2.5'/3.5' HDD & SSD Yottamaster 4 bay hdd enclosure designed for both 2.5' SSDs where speed is the priority and for 3.5' HDDs when it's important to maximize the storage capacity. 6Gbps Transfer Speed This 4 bay hard drive enclosure adopt SATA III protocol,transfer rate up to 6Gbps (MAX). Supoort UASP, which makes it 20% faster than conventional USB 3.0.Compatible with most Windows and Mac systems. Additional Storage Space Expand the capabilities of your laptop/computer and declutter your workspace with the 4 bay hard drive docking station. 80 mm Silent Fan The 4 Bay USB 3.0 SATA hard drive enclosure is all Aluminum design. Built- in 80 mm silent fan; With front and rear Meteor cooling holes.