... -reducing valve and safety valve.Compact in structure,fancy and safe. u Adopting unique design of combination of pressure-reducing valve ... and safety valve.u Compact in structure, fancy and safe, equipped with flow regulator, stable output pressureu Included 1PC nasal ... bridge and 1PC special spanner.u Packed in aluminium-alloy box, strong, wearable . BOX TYPE OXYGEN CYLINDER (STEEL)