Glocks have staggered magazines, with each bullet diagonal to the one beneath it, which makes them bulkier, but gives them higher capacity, about 13 or 15 rounds, I forget which. That’s a standard feature.
Glock 42 is a 380 pistol with a single stack magazine. It normally has a 6+1 capacity but mags with extenders can be bought that doubles it. There is also a Promag 32 round drum for it.