Cantilever rack arms are what hold the material. They attached to the tower at user defined heights depending on what type of material is being stored. Arms come in varying lengths and capacities which is also determined by what type of material it is. Cantilever-racks.com manufactures both straight arm (2-4 degree incline), which is good for material that doesn’t roll, or an inclined arm (22 degree incline), which is typically used for pipes or other rolling objects. We also offer pipe stops which is a 12 or 16 inch pipe that will also stop material from rolling off. Below is a capacity chart for our cantilever rack arms.