Close Nipple -Called a close nipple because there is no space between the threads. For connecting a 1/2'' ball valve to a union.
Hex Nipple -An excellent upgrade to a standard nipple, These have a hex nut in the center to allow easy tightening and loosening in whatever application it's used!
Spaced Nipple - A stainless steel nipple used to combine two fittings with 1/2" FPT threads. There is a 1/2'' space between threads.