The Cheely Custom scope mount for the Trijicon SRO places the scope on the centerline of the pistol when used on a .830″ classic width 2011 style dustcover. Available in silver or black anodized aluminum. Cut from a solid piece of billet. Limited Lifetime Warranty. Drill pattern is the standard 5 holes @.375” spacing. Includes 5-40 screws to mount to your dustcover.