OMS Single Tank Adapter (STA) Hardware Only SS Features: OMS Stainless Steel Single Tank Adaptor ONLY Simple to Assemble Fits All OMS Back Plate/Harness Systems 3.3lbs in Weight If you frequently switch between double tank and single tank rigs, the OMS Single tank adapter is for you. It can mount on any of our harnesses like the DIR and Comfort II harness as well as our IQ backpack. It can even be mounted on many of the metal backplates on the market today. Constructed out of stainless steel to prevent any corrosion with all necessary hardware to mount onto a backplate.