The SDM R4 is SOLD OUT!     The SDM R4 is a bracket that facilitates mounting two additional 2.5″ drives in a HP MicroServer Gen8. There are also mounting holes for fans across the bottom to help cool RAID/SATA cards. The kit includes all the fasteners needed to install.   With optional Stackers you can run four 2.5″ drives on the SDM R4. The SDM R4 will support four 9.5MM 2.5″ drives. If you want to run four drives on the SDM R4, you need to order SSB stacking brackets