Size: 3.5-inch SAS compartment, NOT for 2.5-inch drive. Part number: 5RW66 05RW66 Key information: Condition: brand new Hard drive interface: SAS. Compatible: server hard drive Compatible with: Dell C6320 C6220 (list is by no means complete) Do not hesitate to tell us whether the tray works for a particular server or not. What is included: 1 x 3.5 "hard drive caddy 4 x drive fastening screws