MagBloks are inserted into the top of an empty magazine to so that the slide lock lever does not lock the slide to the rear when working the slide on semi-automatic handguns. This prevents the need to manually release the slide each time it is racked when dry-fire training. The slide will not lock back when MagBlok is inserted, causing the slide to function as it would if the magazine had ammunition in it. This duplicates the mechanical functionality of your handgun when conducting dry-fire training, preventing unnecessary training scars! Each pack comes with three (3) MagBlok 357 inserts and are for handguns chambered in 357 Sig only. Other calibers are available.
MagBloks should not be used without a BarrelBlok properly inserted into your barrel.