Several M1 Carbines have been issued with a simple L-form rear peep sight, which could alternate among two different peephole heights for a hundred and fifty- and 300-garden ranges. The sight was set in the dovetail atop the receiver and never adjustable. The holster is meant to do the job https://griffinmmkur.blogspothub.com/32421874/the-ultimate-guide-to-daniel-defense-ddm4-v7