Marvel Precision 1911-22lr Conversion Unit 1 Lock Back Series Gov't model with combo rib (pic. rail with adj. target sights) and 5.3 match grade barrel. Fits all full size 1911 frames made to GI specifications. Convert your 1911 45ACP into a match grade 22lr pistol. Comes with test target showing what ammo was used to obtain its less than 1� at 50yd group. Designed for standard-velocity 22lr ammo. Installs in 1 minute. Comes with 1 polymer 10rd magazine.