How is anyone going to shoot a 10,000 round stockpile of 556, without one of these? Think of all the time you'll save reloading those pesky 30 round mags. With a PMAG D-60 you'll think you'er using belt fed. The hurt of sore thumbs from loading mags every 30 rounds. You'll wonder why you didn't buy one long ago. Now you can finally test the heat strength of your AR barrel after a few quick drums.