Features: 1Scope of Application: Great gear for diving, snorkeling, applicable for 8?12L gas cylinder. Depending on the diameter of the cylinder, the screw is lockable. 2Saving Space: When not in use, it can be folded together for storage, does not take up space, easy to carry, and can be placed anywhere. 3Durable Material: Made of 316 stainless steel, it has strong corrosion resistance, high temperature resistance, not easy to rust, and is durable. 4Easy to Operate: Installation is simple and easy, the connection is firm, and the tightness of the bottle retainer can be adjusted through the wing nut. 5Two Types of Screws: One long and one short screw, the short one can be fixed on the top to avoid poking the back and effectively improve the comfort of use. Package included: 4 x Hex Nut 6 x Gasket 2 x Bottle Retainer&nbsp 2 x Screw 2 x Wing Nut