scba breathing apparatus 1.Air cylinder volume:5,6,6.8L 2.Have CCS/ECcertification 3.service time:50-60min 5years experience Self-contained breathing apparatus The RHZK series Positive Pressure Air Breathing Aparatus is a kind of automatic open-type air air breathing device. It is mainly applicable in firefighting , chemical industry, ships and vessel, petroleum, smelting and mine industries. It ...