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Imperial · Air System
90657
In stock · ships from Knoxville
This is a 1/2-inch compression nut used to secure nylon or copper air brake tubing to fittings in heavy-duty truck and trailer air systems.
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 onto the fitting body and compresses a ferrule onto the tubing, creating a leak-proof seal. Replace it if the threads are damaged, the nut is cracked, or if it's missing during hose replacement. Typically made of brass and required to meet DOT standards for air brake lines.
Part Number: 90657
1/2 COMPRESSION NUT
Vendor: Imperial
Dealer: KP Services Crossville
Compatibility, alternatives, and more
Parts commonly needed alongside air system
