1. strengthened Oxyen Cannula. 2. certificate,CE ,ISO13485 3. anti-crush tube,non-toxic PVC,medical grade,flexible. nasal oxygen tube helping breathing oxygen1.Made of non-toxic PVC,medical grade ,tubing color is green or transparent2.Tubing out Diameter 5mm/6mm for your choice, anti-crush 3.Different length available,with 2 connectors to match wide range of respiratory equipment.4.Packed in ...