Mine fits some of my Glock holsters, but not all, so it depends.
When you check out, you'll be asked whether you want to buy extra magazines. If you intend to practice reloads with this thing, you want to say 'yes'. (Initially, I assumed that I didn't need any, wrongly assuming that G17/G22/G31 magazines would work; they don't; they don't drop free, and they barely fit. So, 'yes', you need extra magazines.)
And do the magazines fit Glock magazine pouches? Maybe. Some pouches work, some don't. (Good luck.)