The initials ACU can refer to a number of things. The most common is the Army Combat Uniform. This is the typical shirt and pants issued to soldiers for wearing during combat and during most training activities. The new uniform replaces the previous BDU or battle dress uniform.
The ACU has many style changes from the old BDU style. It is easier to care for. The fabric is a polyester and cotton blend. It is also lighter in color. The combined tan, gray, and green camouflage pattern is less discernible from a distance than the previous darker brown and green of the BDU.
Soldiers deployed to Afghanistan also wear a version of the ACU that is designed to be more fire retardant. It can prevent third degree burns and many second degree burns. The fabric is treated with a compound like permetrhin to help reduce the likelihood of contracting illnesses that mosquitoes carry.
The new uniform is designed with many additional benefits to the soldier. The new uniforms also use infrared management technology to reduce the silhouette from infrared devices. There are patches on the shoulders of the jacket that are sewn in to identify
soldiers. The uniforms sold to the general public in army surplus stores and in other places do not have the sensitive IR patches sewn in.
Many of the insignias and emblems worn by soldiers are attached by hook and loop rather than being sewn on. Some special recognitions are pinned on. The new t-shirt worn under the jacket is sand colored and is made with moisture wicking fabric to help keep soldiers cooler.
The cargo style pants are designed with several pockets and include a space for inserting knee pads. They are usually tucked into the standard Army combat boots. The new ACU is designed for safety, comfort, and protection of soldiers in the field.