This is a U.S. Army M-1965 Jungle Hammock.
Designed for soldiers operating in jungle environments to provide shelter from rain and protection from insects and vermin.
It combines the functions of a bed, mosquito netting, and a waterproof tent into a single piece of equipment.
The item number is 8465-00-782-6723.
It was developed for use during the Vietnam War era.

The U.S. Army M-1965 Jungle Hammock is a Vietnam-era piece of camping and survival gear designed for jungle environments, featuring an integrated mosquito net, a waterproof canopy, and a lightweight, durable construction. It has a unique design with a false bottom for insulation and an enclosed zipper-opening mosquito net for protection from insects. While ingenious, its bulk and a preference for ground sleeping due to security concerns meant it was not widely used on the front lines.
Features of the M-1965 Jungle Hammock
Mosquito net: A fine-mesh, no-see-um mosquito net is attached to and zipped onto the hammock's bottom, providing a sealed sleeping space against insects.
Canopy: A waterproof, coated ripstop nylon canopy can be stretched over sticks placed in the ground, creating an A-frame structure for rain protection.
False bottom: The hammock has a false bottom made of duck fabric that creates a dead air space, helping to insulate the sleeper and prevent mosquitoes from biting through the bottom.
Materials: Constructed from durable materials like Cordura nylon for the bottom and ripstop nylon for the canopy.
Portability: Designed to be lightweight, but was ultimately considered too bulky for easy transport in operational zones.
Operational issues: The hammock was not widely adopted by troops in the field due to its bulk and the preference for sleeping on the ground for security reasons.