Couplings

Expander bushings are used to increase the size of a female threaded port. There are many uses for expander bushings, but they are commonly used to step up the ports on an air tank that are too small for the male thread of another component.  

Threaded Fitting - Female Coupling A Female Coupler is female NPT on both sides, great for creating your own unique fitting. Made of solid brass. Available in 1/8" 1/4"3/8" 1/2"