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Post Onsite · Air System
321P6
In stock · ships from Knoxville
This is a brass drain cock used to drain fluids or bleed air from low-pressure systems on heavy-duty trucks and trailers, such as air tanks, radiators, or fuel/water separators.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
We don't publish fitment for this part yet. Rather than guess, get it confirmed against your truck in under a minute.
It threads into a 3/8-inch female pipe port and opens or closes with a simple handle or pin turn. Drivers and mechanics replace these when the valve seizes, strips its threads, or develops a constant drip that can’t be stopped. Keeping a good drain cock on air tanks, for example, helps make sure moisture is regularly removed to protect the rest of the air system.
Part Number: 321P6
3/8 DRAIN COCK
Unit: ea
Dealer: Post Onsite
Compatibility, alternatives, and more
Parts commonly needed alongside air system
