Rugged case and electronics.
Automatic sensor zeroing and self-test sequence upon start-up
CO level beeper can be silenced if desired
Automatic power-off after 20 minutes extends battery life
Large LCD displays CO levels from 0 to 1000 ppm.
Bright back-light allows easy screen viewing under dim lighting conditions.
Beeper triggers with increasing frequency as CO levels rise.
MAX Hold function stores and displays the maximum CO level