10 1/4" OD Tube X 1/8" NPT Pneumatic Straight Fitting. NPT Thread Sizing Info 1/8 NPT 0.405 Roughly 3/8". 1/4 NPT 0.540 Roughly 1/2. 3/8 NPT 0.675 Roughly 5/8". 1/2 NPT 0.840 Roughly 7/8". Type: Push To Connect Straight Fitting.
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