This is the Highland STA Single Tank Adapter Features: 14 gauge (.074/1.9 mm) 316 grade stainless steel A quick, easy way to mount a single cylinder to a backplate and harness Attaches to cylinder with two cam bands Center-to-center distance of 11" Includes hardware Weight: 1 Pound For divers who frequently switch between double tank and single tank rigs, Highland by XS Scuba&';s Single Tank Adapter is a convenient way to attach cam straps to a hard metal back plate that does not have tank band slots."