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🍁 Fall Savings Are Here – Get Up to 30% Off Select Fittings & Hose!
🍁 Fall Savings Are Here – Get Up to 30% Off Select Fittings & Hose!
Foster PD13-4, 3/8" Industrial Plug x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 4 Series, Steel

Foster 42S-4, 3/8" Industrial Plug x 3/8" Male NPT, 4 Series, Free Swivel, Brass/Steel

by Foster
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$ 12.99
$ 12.99 - $ 12.99
$ 12.99
$ 10.39
$ 10.39 - $ 10.39
$ 10.39

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 42S-4 is a Brass/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: 42S-4
  • Interchange: 3/8" Industrial
  • Body: 3/8" Plug
  • Thread: 3/8" Male NPT, MPT
  • Valve Type: One-Way Shut-Off
  • Material: Brass/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

  • Free swivel under pressure — which means the plug rotates freely to eliminate hose twist on blow guns, air tools, and end-drop applications.
  • Brass/Steel construction — which means it withstands repeated high-pressure cycling without deforming.
  • 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 questions

What 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.

How does the swivel help?
The plug swivels freely even under pressure, so the hose will not kink or twist on blow guns, air tools, and overhead drops.

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.