This is the first type Springfield 45-70 rear Carbine sight. These are the sights that were used on Custer’s Carbines at the battle of little Big Horn. It will fit and function perfect on any Springfield 45-70 Trapdoor. Excellent Condition with deep clear marking. The ladder has 12 elevations and the base has 5 elevations. These elevations were designed for the Carbine. The ladder flips up easily and the elevation slide works great This is an original Springfield Model 1873 45-70 Trapdoor rear sight. It was designed for the early Model 1873 Carbines. It will also fit all Models including 1873, 1877, 1878, 1879 & 1884 Carbines. Use mounting screws (ORI-332) for this sight