I run gen 1 mags that hold 16 rounds in my G20. With these extensions, that puts me at 21 rounds.
My 20 year old plus 2 extensions are showing signs of falure, with the lip on one breaking off on one side. Not good. No use having extra ammo, if it all ejects out the bottom of the mag.
In looking for replacements, I ran across these that hold more ammo, never a bad thing.
They were back ordered when I placed my order a week ago, but today, they shipped!