OMS 186mm Stainless Steel Twinning Bands A16610422 Pair of OMS Stainless Steel Cylinder Bands to fit  10.6 & 11.1 Litre - 80 Cubic Foot Aluminium Cylinders with a diameter of 186mm. Manufactured from Marine Grade 3162 Stainless Steel and supplied complete with all Bolts, Washers & Nuts. For sturdy construction of a Diving Twin Set and secure attacment to B.C.D's and Tech Weight Harnesses.