1. Use a unidirectional oil-free self-lubricating vacuum pump as a negative pressure source, no oil pollution, no positive pressure in the pressure system
2. Negative pressure system can be adjusted according to the consistency of sputum and mucus
3. Equipped with overflow protection device and intermediate pipe to prevent inhalation of liquid
4. The filter protects the negative pressure pump from contamination
5. Durable, attractive, easy-to-clean, and infection control friendly