1/2 in. x 3/4 in. Brass Sprinkler Extension (12.7 x 19.05 mm) is machined from a single piece of solid brass to extend the distance between a fire sprinkler's thread connection and sprinkler system piping. Used when a drop nipple has been cut too short or to accommodate variations in drop ceiling height, this extender features a 1/2 in. (12.7 mm) female NPT connection, a 1/2 in. (12.7 mm) male NPT connection, and is 3/4 in. (19.05 mm) long.