TWA and STEL readings with lunch-break mode.Up to 600 hours of datalogging with alarm trends.High impact protective rubber overmolding.Lithium ion or alkaline power source (interchangeable).Calibration reminder with lock out option.Pump pause on demand extends battery life.Internal sample drawing pump with up to 50 foot range.-Pump active, microprocessor status and battery level.Snap-logging - on demand data recording.Auto-ranging display of % LEL and % volume.
