Antares 2
Antares 2 (X-259) was an American solid rocket engine stage and engine built by Hercules/ABL / Thiokol. It was used from the mid-1960s to 1995, in the Scout and Strypi family of rockets, and on the Project FIRE Velocity Packages. It burned solid propellant – the stage was also the engine's fuel chamber - and was used about 96 times.