9 Steps Stair stringer is a set of 2 stringers, 1 of 4 steps article 308771923 (model 13904), 1 of 5 steps article 308771936 (model 13905) and 1 stair stringer connector article 80645119 (model 13920), allows the construction of a solid and durable 9 steps staircase component. A wooden support (4 in x 4 in) is required, not included. Once assembled this stair stringer is ready to receive steps in steel, fiberglass, wood (use 2 x 2 in x 6 in boards or 1 x 2 in x 12 in board), etc. Lightweight and easy to handle, it sets up quickly and easily. The stair stringer is powder coated paint offering excellent rust resistance. Ideal for a 75-in high structure, it is also suitable for a structure between 71 ½-in and 78 ½-in high. The stair stringer allows for the installation of a 11 in deep steps. Maximum spacing between stringers: 54-in for residential project. Please contact manufacturer for commercial projects. The set included 1 Stringer of 4 steps, 1 Stringer of 5 steps and 1 stair stringer connector. Allowable load of 100 lbs per square foot and ultimate load of 144 lbs per square foot. Color: Black.