Hey guys, I'm not 100% sure about this, but from my knowledge, this seems right. I've heard so many people say the Glock 39 (.45 GAP) has the same Specs as a Glock 26, 27, and 33. Well, if I'm not mistaken, all websites are just stating what Glock.com is generally stating about their models saying that all the slides have a width of 1.18 inches. Well, I also checked the websites for the width of the Glock 19... all stating that it has the same width, 1.18 inches. I also held a Glock 26 and 27 side to side with a Glock 19 and 23 all having the same slide width seen with my eyes at least. Well... if this is true, all the websites stating that the Glock 39 has a width of 1.18 inches are false. I have pictures to compare. (Keep in mind, the Glock 26 and 27 have the same slide width as the Glock 19 and 23): Top: G39 Slide, Bottom: G19 Slide Left: G39 Slide, Right: G19 Slide Left: G39 Slide, Right: G19 Slide It is clearly obvious that the G39 Slide is thicker in width compared to the G19 Slide (Substitute for the G26, 27, 33 Slide). I measured both, G19 measuring roughly at 1 inch, and the G39 measuring at roughly 1 1/8 inches. If this is a invalid state/study/input please correct me if I'm wrong, but I'm just sick of people saying they are the same size because they only base this off of what they read on the internet. If this were true, my G39 would of fit into a Glock 26, 27, 33 Holster... instead it only fit into a G30 or 29 Holster (due to slide thickness). To me, its only common sense... a bigger calibar, a big slide... Please comment !