Foster PB5-4, 3/8" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster PB5-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flow quick coupler that interchanges with any 3/8"-body industrial-interchange half (ISO 6150-B / ANSI T3.20.14). Built in the USA for shop air, tools, and production lines that demand dependable, high-flow connect/disconnect.Specifications Brand: Foster Series: 4 Part Number: PB5-4 Interchange: 3/8" Industrial Body: 3/8" Plug Thread: Reusable Hose Fitting, 1/4" ID x 9/16" OD Valve Type: One-Way Shut-Off Material: Steel Operation: One-Way Shut-Off plug (un-valved; mates with valved socket) Working Pressure: 300 PSIG; vacuum to 27" Hg Temperature Range: -40°F to +250°F Seal: Buna-N (Nitrile) Quantity: 1pc Origin: Made in USA Why this plug Steel construction — which means it withstands repeated high-pressure cycling without deforming. Reusable hose fitting — which means you can re-clamp it onto a fresh hose instead of scrapping it. One-Way Shut-Off — which means the socket seals the supply line the instant the plug is removed, holding pressure and preventing blow-down. Snap it on and the connection just holds — full 3/8" flow, no drips, no hiss. Built to take daily shop abuse and keep sealing leak-free, connection after connection.Frequently asked questionsWhat does this connect to? It mates with any 3/8"-body industrial-interchange coupler (ISO 6150-B / ANSI T3.20.14) — the most common air-coupler standard in North America.What pressure and temperature is it rated for? 300 PSIG working pressure (vacuum to 27" Hg connected), with a Buna-N (Nitrile) seal.Is this air coupler fuel-rated? No — the 4 Series is an industrial air/fluid coupler for compressed air, water, and similar media; it is not rated for fuel.What hose does it fit? It is sized for hose with 1/4" inside diameter and 9/16" outside diameter. The reusable clamp grips the hose OD; no separate crimp needed.Ideal for shop air lines, pneumatic tools, impact wrenches, and production equipment. Pair this plug with a matching 3/8" 4 Series coupler for a complete, leak-free connection.Why buy from hpcouplers: Foster quality (an Ideal Tridon Group brand), backed by responsive US-based support, accurate specs, and fast shipping. Quick-coupling is what we do.