The Vitalograph child peak flow meter is a lightweight, robust and accurate meter designed for children. The child peak flow meter is designed with easy to read scale markers and is designed to be used with SafeTway mouth pieces for hygienic use. Variable orifice flow meter with movable pointer Scale Interval : 10L/min below 700, 20L/min. weekly Flow Range : 50 - 800 L/min. Meter Size : 13.7cm x 6cm x 3.4cm.