... diameter 406mm. Zhejiang TianEn Pressure Vessel Co.,Ltd is a Professional Manufacturer of Seamless Steel gas cylinders, CNG-1 cylinder in Zhejiang, China . ... 150L.Out Diameter :232MM, 325MM, 356MM ,279MM,406MM .Wall thickness :5.5MM ,6.4MM,7.6MM,8.2MM, 8.8MM,9 ... .0MM.Material :34CrMo4 ,30CrMo. Other speciifcation also available for customers requirement .Welcome to inquiry us . We will reply you ...