Sure-Lok GO2 - Dual O2 Cylinder Holder Ergonomic tightening and release knob for ease of use Visual lock indicator to help ensure the GO2 is secured Two anti-slip straps to hold O2 cylinder in place while in transport Quick release for easy height adjustment to accommodate O2 cylinders from size M2 to E High grade anodized aluminum for durability and resistance to corrosion Series L Track fitting mounts easily on vehicle floor and moves from one vehicle to another without the use of tools Weighs less than 6 lbs. and iscompact in size for ease of transportation and storage