The Lightweight Environmental Protection (LEP) is an insulation subsystem developed under the Special Operations Forces Personal Equipment Advanced Requirements (SPEAR).The system is designed to be individually configured based upon mission, terrain and climate requirements as well as personal preference.

The LEP layer 1 silkweight undershirt and drawers are intended for wear as a moisture wicking layer of the ECWCS.

The LEP layer 2 midweight undershirt and drawers are intended for wear as an insulation layer of the ECWCS.

The LEP layer 3 midweight stretch bib overall is intended for wear as an insulation layer of the ECWCS.

The LEP layer 4 fleece jacket is fabricated in a heavyweight fleece fabric. It has a collar, zipper front closure, pit zips, two zippered hand warmer pockets, inner pockets and a windproof front and back yoke.

The LEP layer 5 wind resistant fleece jacket is fabricated in heavyweight fleece wind resistant fabric. It is the same basic design as the layer 4 heavyweight fleece jacket with the addition of wristovers and a hood.