Steel Hex Headless Plug 1/2 Inch NPT Male, PK 50 These Steel Headless plugs are manufactured with threads that confirm to the American standard taper pipe thread and have a good resistance to vibration and pipe movement..
.1/4 Inch Lincoln Series Brass Coupler x 1/4 Inch Male NPT, PK 100 These couplers are interchangeable with the Lincoln Standard series couplers produced by other manufacturers. Precision machined from solid brass bar stock which provides longevity during mechanical shock in rugged applications. Interstate Pneumatics 1/4 Inch Lincoln Brass Coupler x 1/4 Inch Male NPT.