Attributes . The stem part that is clamped to the hose is one part of the Boss Washer Seal connection. The Boss Washer Seal spud part of the coupling serves as the other half of the connection and is usually fixed to the equipment. The two halves are connected or disconnected by rotating the wing nut on the spud. A Leakproof seal forms by rotating the wing nut and hammering it tight. Easy to seal. A Klingersil? C-4401 washer is inserted between the stem and spud. . Names