Originally Posted by Bump_Pitch
But could you give me more explanation with the PVC, I'm not familiar with geos
PCV, not PVC.
Purge control valve. When you degas the gun, if all the air just rushed out the ASA, the market would actually fire a shot (if you're familiar with spool valve markers you'll know why, if not that's a discussion for a different thread). The PCV let's the air out slowly, thus keeping the marker safe. That's why Geos hiss for a few seconds when the air is turned off.