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Mid-America · Air System
321P4
In stock · ships from Knoxville
This is a 1/4-inch male NPT external seat brass drain cock. It is used to drain moisture and contaminants from air tanks on heavy-duty trucks, trailers, and other air systems.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 2 applications
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All confirmed applications for this part number.
Other applications
Other applications
Universal fit for any air tank equipped with a 1/4" NPT female drain port. Commonly used in commercial vehicle air brake systems.
Part data verified against 2 catalog sources
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The external seat design allows a simple quarter-turn to open or close the valve. Replace it if the valve becomes stuck, leaks, or the handle is damaged.
Part Number: 321P4
1/4 DRAIN COCK
Unit: ea
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside air system
