The All Purpose Environmental Clothing System (APECS) parka and trousers were developed to provide Marines with an all-purpose/all-season set of outershell garments that are lighter in weight, lower in bulk, have lower noise generation, are moisture vapor permeable and have an improved water repellency over the 2nd Generation ECWCS parka and trousers. The parka has a collar with a draw cord for adjustment and a stowed hood, water-resistant slide fasteners are used in the front closure, underarm openings and the two concealed upper chest pockets, two lower pockets with flaps and concealed hand warmer pockets, two upper sleeve pockets with flaps, adjustable wrist tabs, an insignia tab on the left front, and draw cord adjustments for the waist and hem concealed inside the lower pockets. There are reinforcement patches on the elbows. The parka is also designed to accommodate an optional detachable hood with fur ruff for use in extreme cold weather.