Pipe Plug Brass 3/4 in. NPT | Barr Marine 50-091-075 Barr Pipe Plug Brass 3/4 in. NPT | Barr Marine 50-091-075 Solid hex head brass plug used to plug exhaust manifolds & risers. Barr 3/4 in. NPT brass plug 5/8 Hex socket recess Replaces Crusader 113177 Replaces Westerbeke 36849 , 207782