Front Door (window or solid steel): Composite frame (injection molded top and bottom with extruded composite sides) 140-degree opening door Field-reversible (left or right) hinge Quarter-turn key lock, two keys included Window door is scratch-resistant 1/4-in. tinted safety glass Solid door has 16 gauge steel insert with matching black finish Center Section: Welded 14 gauge steel Solid top of center sections provides protection against falling debris Ventilated sides (to which fans can be added) Self-latching closure connects center section to wall section Self-alignment ramp supports center section to wall section Heavy duty center-to-rear section hinge with quick-release self-retained hinge pin eases wall installation Rack-Mounting Angles: 12 gauge, plated steel EIA universal spaced 19-in. rack-mounting holes RU marked from bottom to top Tapped 10-32 holes, 20 mounting screws included Rear Wall Section: Welded 14 gauge steel Radius corners; no sharp edges Available with knockouts or gland plates Raised pads for accessory mounting Cable tie-down points for cable management Keyhole mounting holes allow wall section to be mounted over fasteners and eases installation Three cable-entry grommets