Removal of the rear take-down pin allows the receivers to be opened by rotation around the forward pivot pin as a hinge. Finally, the quality of the hardcoat anodizing Schliff can make or break your build. A consistent, deep black Schliff that will match well with other hardcoat anodized components https://andydjnru.wikipowell.com/5067835/neue_schritt_für_schritt_karte_für_80_lowers