Air-Kaddy is a unique modular alluminum design that allows for expansion as needed to accommodate your storage needs. The unit is available in 2 styles, one for free standing that holds up to 40 SCBA cylinders and a smaller style for vehicles holds up to 24 SCBA cylinders. All racks are linded with nylon pads to prevent cylinder scratches. Custom sizes are available. Thread Saver, cylinder thread protectors, are availble as an option.