Leapers RBT-GL933: These are some of the nicest standard or extended capacity aftermarket pistol mags I have ever seen for the Glock Pistol. They are manufactured by Leapers UTG who is quickly becoming a leading force in gun parts and accessories. We have tested all of the various UTG mags here extensively and find them to be of very high quality and comparable to the original Glock mags in fit and feed.