all are hem designed so as to protect your hands; super space inside fit for every kind of motherboard; EMI interface design to avoid electromagnetic radiation; 8cm, 9cm, 12cm fan on front for optional; 2*8cm fan on rear case for optional; buckle lock design preventing hardware missing; thumb-screw for easy open or close of side panel; air-duct for optional on side panel; USB2.0 & audio on front panel.