High-test Peroxide

High-test peroxide or HTP is a high (85 to 98 percent)-concentration solution of hydrogen peroxide, with the remainder predominantly made up of water. In contact with a catalyst, it decomposes into a high-temperature mixture of steam and oxygen, with no remaining liquid water. It was used as a propellant of HTP rockets and torpedoes, and has been used for high-performance vernier engines.