Hi, new member here. I did a quick search on this issue and didn't see anything but I apologize in advance if it's been asked before. I returned some 13 rd .40 magazines to Glock for my 23 that were giving me feeding troubles and the ones I got back have a 2 next to the Glock logo on the round count side of the magazine. I checked my others and they have a 1 there, otherwise they look identical. What is the difference and is one better than the other?