3PCS 5/16"×1/2"(8mm×12mm) Hose Barb Union Splicer Brass Pipe Fitting Reducer Straight. Small End Barb OD 5/16" (8mm). Large End Barb OD 1/2" (12mm). Installation Reminder : Must use a hose clamp, crimp sleeve, or ferrule to fix the barb-hose joint (accessories not included), especially for high-pressure scenarios such as air compressor pipelines, to prevent disconnection and leakage.
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