100% medical grade PVC material, PP for connector and oxygen reservoir bag. Clear for visual assessment. Extra comfort for patient better fit. Kink-free, crush-resistant tubing. A low-resistance check valve which prevents rebreathing and allows exhaled gas to escape. Comes with or without 7 Ft of kink-free oxygen tubing. Available in 2 sizes of adult and child. Material: DEHP free, Latex-free. Under-the-chin design for excellent fit on a wide variety of face sizes.