Model No. SST-RM41-506 Chassis form factor 4U Material SGCC Motherboard CEB (12" x 10.5"), ATX (12" x 9.6"), Micro ATX (9.6" x 9.6"), Mini-ITX (6.7" x 6.7") Drive Bay External 5.25" drive bay x 6 Internal 4 x 3.5" 2 x 2.5” (up to 15mm) 1 x 2.5” (up to 15mm) or slim optical (12.7mm) Power Supply PS2 / ATX / Mini Redundant (supports up to 160mm) Expansion card Compatible up to 7.9” (200mm) in length Limitation of CPU cooler 148mm Expansion Slot Standard profile PCI / PCIe x 7 Front I/O Port USB 3.1 Gen1 Type-A x 2 Front buttons Power On / Off, system reset Indicators Power status x 1, HDD activity x 1, LAN activity x 2 Main metal thickness 1.2mm Net Weight 9.7 kg Dimension 430mm (W) x 176mm (H) x 446mm (D) 16.93" (W) x 6.93" (H) x 17.56" (D)