BNG series explosion-proof flexible connection. Tube 
 Scope: 1 and Zone 2 dangerous places. IIA, IIB, IIC explosive gas environment 
 Features: a fire, corrosion resistance, water resistance, aging resistance, flexible and firm structure, work reliable. The length, thread size can be specially designed. Such as NPT, metric thread and so on. Note: should indicate the size marked inside and outside the screw thread. If: CBR-700 X G3 / 4 "(inside) / G1" (external) means a length of 700, one end of the thread G3 / 4 ", one end of the external thread G1" rubber sheath flexible connecting pipe. meet GB3836-2000, IEC60079 standard request.