All aluminum construction; Stainless steel and automotive-grade hardware; Ample T-channels; Full and mid-height options included; Telescoping crossbars may be mounted on top of the frame with an adjustable height accessory kit; T-channel and J-hook mounting hardware included; Not compatible with RamBox Beds or GMC Sierra CarbonPro Beds; 1200 lb Static weight capacity; Adjustable height crossbar kit