The US military UCP bivy cover is a waterproof and wind-resistant outer layer designed to protect sleeping bags in the field. It is part of the Modular Sleep System and can also be used as a stand-alone bivy sack.

• Pattern: Universal Camouflage Pattern (UCP)
• Material: Waterproof, breathable laminate fabric
• Compatibility: Modular Sleep System (MSS) patrol and intermediate sleeping bags
• Function: Provides weather protection and concealment in field environments

Issued to U.S. Army personnel as the outer shell of the Modular Sleep System during the UCP uniform era.