GOG Paintball 360 Degree Swivel QEV 4mm for Extcy, G1, Envy - Silver by GOG Paintball. $24.09. Description Quick Exhaust Valve that swivels 360 degrees for installation at any angle. The 360 QEV also increases cycle rates and shots per tank, while decreasing dwell and input pressure. Fits GOG Extcy, G1, Envy.