Effective Medication Utilizing two oxygen concentration dials, our Venturi-style masks deliver nine specific oxygen concentrations ranging from 24% to 55% O2 . They accommodate pediatric and adult patients. Each mask comes complete with 7' of crush-resistant oxygen tubing, 6" flextube, color-coded low and medium concentration dials, a high-humidity adapter and a humidifcation hood. For use with 50 psi oxygen source and flowmeter.