The AFM (ALG Flared Magwell) is used to make speed reloading faster by decreasing the precision needs to insert a magazine into the pistol. Additionally, the flare of the AFM acts as a ledge to spread the recoil impulse into the bottom of the gripping hand. The ALG Flared Magwell (AFM) is designed to fit Gen 3 Glock 17 and 22 pistols. It will not fit Gen 4 pistols and its compatibility with other Gen 3 Glock pistols is unknown. Mfg: Alg Defense SPECS: Material: Hardcoat anodized aluminum.