A4000 LFST is a heat shrinkable lay-flat tube which has been oriented in the transverse direction. When exposed to heat 249 to 348°F (121 to 176°C) in a recirculating oven, tunnel oven or from a heat gun, the A4000 LFST material will shrink to closely fit the mandrel. A4000 LFST is ideal for providing a self-releasing cover for mandrels used in fabrication of hollow composite parts. A4000 release film is an approved material on all major aircraft specifications.