We are a professionalManufacturerof Seamless Steel gas cylinders, CNG-1 cylinder in ChinaThe specification of our Seamless Steel gas cylinder as following :Production standard : GB5099 ,ISO9809Working Pressure :15Mpa ,Testing Pressure :22.5MPa ,25Mpa Water Capacity :4L ,5L ,6.3L,8L ,10L ,15L ,20L, 32L ,36L,38L ,40L, 45L,47L,50L .Out Diameter :140mm, 159mm ,219mm ,267mm,279mm, 232mm.Wall thickness :3.6mm, 4.5mm, 5.7mm ,6.0mm,5.5mm.Material :37Mn ,34CrMo4.Packing: Bare In loose , Each piece covered with a plastic net bag.