Ref. main specs on 40L O2 Gas Cylinders: -1). Water capacity: 40 Liter; Mat.: 37Mn; OD= 219 mm; W. P/T. P.: 15/25Mpa; Wall thickness: 5.7 mm; G. W.: ~47kg; Height: 1, 345 mm (W/O cylinder cap); Gas(O2): 6M3. -2). Color: As GREEN preferred; -3). Connecting thread: -4). Applied standard: ISO 9809-3; -5). Packing: Each with nylon bag or as preferred(based on bilateral agreement). What we can promise for you: *High quality and security gas cylinders; *Competitive unit price in the market; *Fast delivery (3~4 weeks); *Best after-sale service.