Antec Sonata Elite Black ATX Mid Tower Computer Case 7 Drive bays - external 3 x 5.25, internal 4 x 3.5, & included 5.25 to 3.5 adapter for external 3.5 device 2 Layer, steel with polycarbonate, side & top panels to deaden noise 7 Expansion slots Advanced cooling system - 1 rear (standard) 120mm TriCool 3-speed switch control exhaust fan, 1 slot 120mm exhaust blower with 3-speed switch Built-in washable air filter