I used this to fix one of my KWA G19 mags that leaked gas from the fill valve. At first, I thought I could just reseat the valve, but replacing this valve fixed the mag permanently. I mean it can now hold gas pressure for days, not hours.
Remove the base plate first before removing old one and installing. A flathead screwdriver is all you need to tighten this in. The o-ring seems bigger than stock. But, my problem was with the internals with the fill valve on the old one.
Works great and is an easy DIY fix. My old fill valve hisses if held close to the ear.
Pricey for a little part. Any more money, and I would consider buying a new mag.
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