Wildcat air bleeder hole

Hi Jibeji,
Actually there is a Delrin seat that goes in the air bleeder hole that the gauge is tightened down on. It is what creates the seal... not an o-ring. Here is the part number taken from the Wildcat parts sheet and some pictures for you. The part number is: B9 5005 Plastic washer 2mm / http://www.fxairguns.com/wp-content/uploads/2015/10/wild-exploded-drawing-AoA.pdf

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