1.being approved by ISO11439 2. cng cylinder 3. The length is 1378mm(without valve) Our company has a military background, it possesses the manufacture licenses of cng cylinder for grade B1,B2,B3,D1 and D2, as well as perfect quality control system. The safety technical index have reached a leading level both in China and in the world with being approved by ISO9001:2000,ISO/TS16949:2000,DOT,BV, ...