This receiver sight, based on Lyman's famous 1895 patented Model #21 sight, is designed to operate on most models of Marlin Lever Action rifles. Consisting of machined steel and brass components entirely made in the USA, the sight comes with what you see plus three full pages of instructions. If you have one of the foreign made rifles you will need to purchase our tap item#PTCTAP to retap the forward hole and to thread the rear hole.