MSA Air Respirator Explosion-Proof Filling Cabinet, designed and manufactured in accordance with the National Fire Protection Association (NFPA) standards; ergonomically designed; door interlock device automatically cuts off the filling circuit when the door is opened and restores it when closed; self-locking mechanism prevents the door from being accidentally opened during cylinder filling; cylinder bracket features a rotating structure with pneumatic springs for easy operation and reduced operator workload; equipped with 2 or 4 filling hoses, each with a filling valve and pressure gauge; capable of simultaneously filling 2-4 carbon fiber cylinders, compatible with 6.8L, 9L, and 12L cylinders. MSA Air Respirator Explosion-Proof Filling Cabinet features: 1. Double-layer cabinet structure: outer cabinet made of double 5mm steel plates; 2. Compatible with both 6.8L and 9L carbon fiber cylinders; 3. Self-locking door mechanism prevents unintentional opening during cylinder filling; 4. Filling hoses and valves allow flexible selection of the number of cylinders to fill based on needs; 5. Door interlock device automatically cuts off the filling circuit when the door is opened; 6. Rotating cylinder bracket with pneumatic springs reduces operator workload; 7. Pressure relief holes in the inner layer and bottom of the cabinet allow gas discharge from the bottom, preventing harm to personnel. Extended functions: 1. Pressure regulation capability; 2. Stepped fully automatic filling control system for cylinders; 3. Cylinder bundle, including cylinder pressure gauge and cylinder valve.