These tubes are made of polyurethane (PU), which ensures that the flexibility of the tubes is not affected by heat and guarantees a long lifespan. The tubes are smooth and easy to pass. The rounded edges at the nasal tip help reduce the risk of tissue damage. The other end is uniquely shaped and corrugated for secure and easy connection with both the stomach pump, funnel, and activated charcoal bottle. Easy to clean and can withstand all standard disinfectants. Harmless side holes (2).