Simple, easy-to-use design lets you load pistol magazines quickly without dinging the feed lips and pinching your fingers, so you spend more precious range time shooting, less loading magazines. A real life saver for squeezing those last few rounds into mags with heavy springs. Slide the loader over the magazine and grasp both firmly as you repeatedly depress the ribbed, no-slip thumb lever to relieve the spring pressure and insert rounds. Depending on model, a slot or an adjustable stop in the loaderÂ?s base prevents movement of the magazine while loading.