... coal mine underground One, product characteristicsIn 1, HCBK-4 explosion-proof amplifying communication system using ZL102 aluminum alloy die-casting ... , intrinsically safe type liquid crystal state display window, the magnetic induction of high reliable on-hook switch, mobile phone, ... IEC60079-11, EN50014, EN50018, EN50020/392: Exdib II BT6, explosion proof mark is equivalent to the II 2G Exdib II BT6 ...