Muorka Adjustable Aerobic Stepper Fitness Exercise Platform Workout Equipment W/ 4 Risers-30",Black&Grey Ideal for cardio workout or to strengthen your lower body, Perfect for indoor and outdoor use. Color: Black + Gray, Red Signal, Material: ABS Step Platform Size: 31" X 10.6" X 3.5" (L X W X H) Adjustable Height: 4", 6", 8" Shock absorbing, non-stick, non-slip surface.