This is an experimental rocket motor nozzle, manufactured by the Reaction Motors Division of the Thiokol Chemical Corporation. Developed in the 1950s, nozzles like this one were used to test motor designs for RMI's full line of liquid fuel rocket engines for civilian and military applications. Engine thrusts ranged from less than one hundred pounds to many thousands of pounds.
Transferred to NASM from the Thiokol Chemical Corporation.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.