1.industrial telephone suit for arduous and hadzardous. 2.new fashional than others 3.Industrial telephone :IP67 4.EX 1 Application 1.1 The hazardous location of explosive gas mixture , Zone1, Zone 21.2 explosive gas mixture , 1A 2B IIC* 1.3 temperature group ,T1-T61.4 Ambient temperature,-30 ~ +501.5 degreeRelative humidity, ≤95%1.6 Atmospheric pressure, 80~110Kpa 1.7 Defend grade, IP 672.Main ...