... reducer,Warning whistle,Pressure Gauge,Back plate and cylinder. For field operation respiration. Has thermostablly, flame retardant, insulation, ... good properties. Cylinders work pressure,30Mpa .back frame for high strength of nonmetal materials, level pressure reducing valve ... piping connections can be 360º free rotate, suitble for various situation. Users replace cylinders unarmed, do not need any ...