Marbles Arms tang sight (aka Peep Sight) Remington Rolling Block RB1 CURRENT PRODUCTION and UBERTI factory produced ROLLING BLOCK rifles sold by other companies in the US like Cimmaron, Taylor, and others. The tang sight comes with 3 different sight apertures (1/2 inch diameter with .076 hole; 1/2 inch diameter with .102 hole; 3/4 inch diameter with .032 hole). Hole spacing on the base of the sight is 1.937 inches and the height adjustment is 2.415 inches to 2.750 inches with a 21 degree angle on the upright. Mounting screws are NOT INCLUDED with the tang sight, so if you need those screws they can be purchased in the option box below.