This is a JATO (Jet-Assisted-Take-Off) unit known as the JATO Junior developed and built by the Aerojet-General Corporation of Azusa, CA. It was meant to assist the take-off of light planes making short field takeoffs or emergency climb maneuvers. The JATO Junior was developed by Aerojet from 1951 and produced 350 lbs of thrust for 12 seconds. Such JATOs were continued to be used into the 1960's. Versions of it are still used today.
Aerojet General donated this JATO to the Museum in 1968.
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.