The heat-reactive synthetic rubber materials covered by this specification are intended for use in a wide range of applications requiring a tough, flexible synthetic rubber that will reduce to predetermined dimensions upon application of heat and will maintain good physical and electrical properties after heat shrinkage. Some usages include identification and covering splices in cables, lugs, pipes; protecting feed-throughs; jacketing of assemblies; insulating pigtail connections; sleeves for wave guides and rectifier leads; and covers for resistors and diodes.

The heat-reactive synthetic rubber materials covered by this specification have unique military requirements in that some types and classes must be resistant to chemicals such as hydrazine/UDMH (MIL-PRF-27402), nitrogen tetroxide (NHL-P-26539) and nitric acid (MIL-P-7254), that are used as propellants in missiles. All types must be resistant to fuels and oils such as JP-4 fuel, hydraulic fluid (MIL-H-5606), lubricating oil (MIL-PRF-7808) and aviation gasoline 100/130, that are used on military aircraft. All types must be functional over military temperature ranges, which exceeds that required in the commercial market.