Three (3) Palmetto State Armory Micro Dagger 15 round magazines.

These also work with the Glock 43x/Glock 48.

Full disclosure:

I had a malfunction (FTE) with the stainless magazine and (FTF) with one of the phosphate magazines. Each magazine has been cleaned and has approximately 200 rounds through each. I have decided to stick with OEM. If you'd like to try these for your platform and see if these would work for you at a discounted price, this is a good way to go. 
I would like to get 60 for all three. 
Thanks for looking.