The Space Shuttle's Reaction Control System (RCS) provides the thrust for pitch, yaw and roll maneuvers as well as for small velocity changes of the orbiter.

In addition to the 38 primary RCS engines, there are six Vernier RCS (VRCS) thrusters used for fine adjustments of the orbiter's attitude. Two VRCS thrusters are located in the nose, while four others are located in the tail.

Each RCS engine contains a fuel and oxidizer valve, injector head assembly, combustion chamber, nozzle and electrical junction box.

The vernier engines' reusability depends on chamber life. They are capable of sustaining 330,000 starts and 125,000 seconds of cumulative firings.

This VRCS nozzle, which was cut from a flown RCS unit, was scrapped by NASA to be recycled.