Two lightweight 12 Litre steel cylinders, manufactured to the stringent standards of the European Community PED specification with a maximum Working Pressure of 300 Bar. Supplied complete with a M25 X 2 EN-144-3 manifold with dual 300 Bar G 5/8 DIN outlet valves and integrated central isolator , high tensile polymer twin boot to allow vertical storage when not in use & stainless steel bands with extra long stainless steel threaded bar, washers and nuts. Everything you need to assemble a twin set with a total capacity when fully charged of 7200 Litres of gas, supplied Oxygen cleaned and ready for use with Nitrox or Trimix if assembled in an appropriate environment with O2 clean valves & equipment. Total empty weight including cylinders, manifold, twin boot, bands and stainless steel attachment nuts and bolts = 40.7 Kgs.