ICY DOCK MB561US-4SB-1 4 Bay 3.5 SATA to eSATA (Port Multiplier) and USB Aluminum HDD Enclosure for Mac & PC. For 4x 3.5 SATA Hard Drives 1x eSATA port (Port Multiplier) 1x USB 2.0 port (Plug & Play)Detachable 80 mm rear fan Fan speed control with smart cooling technology