Macho Seat Mount Hinge - Black The evolution of Biltwell's 4130 chromoly seat hinge, Second-generation welded seat bracket now features an even tougher investment-cast steel pivot head, Cast chromoly hinge head, Laser-cut 4130 chromoly steel strap, Seat bracket is black electroplated for durability, Raw steel pivot bracket and bronze pivot brushings, Retrofits to both the welded and newer cast hinge bung so upgrades are easy, Chrome shoulder bolt