The Halcyon Single Tank Adapter is made from stainless steel and is used to secure a single tank to a wing and backplate. The single tank is fastened with the 2 Halcyon tank straps that are included in the kit. The Single Tank Adapter can be combined with the Halcyon Single Tank Adapter Weight of 6lb (2.7kg), which enables you to reduce weight from your waist and encourages a more comfortable in-water position. The weight can be easily removed for travelling.