How do you know which you have between the two??Mine came with two mags,one was the 15 rounder,the other a 10 round.It also had the cheap plastic grips,which i have already replaced.But on one side of the the slide it says Made in Czech Republic CZ 75B...and the other side of the slide between the two sets of serial numbers,it says(in silver lettering) CZ-USA,Kansas City,KS.