These peak flow meters meet or exceed ATS standards for accuracy and precision. They offer an integrated three-zone asthma management system recommended by NAEPP that helps patients comply with treatment regimens. The color-coded indicators can be adjusted to delineate a patient's green, yellow and red zones based on a personal best peak flow. Available in full (60 to 810 L/min in 10 L/min increments) and low (50 to 390 L/min in 5 L/min increments) ranges, both with companion card.