Aircrew Survival Egress Knife

The Aircrew Survival Egress Knife or ASEK is a U.S. Army aircrew survival knife, designed and initially manufactured by the Ontario Knife Company, and entered service in 2003. == Features == The ASEK has a number of features set by the United States Army Aviation Branch that aid in escaping an aircraft, such as the ability to be used as a hammer to break acrylic glass cockpit windows and cut through an aircraft's aluminium skin or electric cables.

Source: Wikipedia — Aircrew Survival Egress Knife (CC BY-SA 4.0)