Color changing pulse oximeter lets you keep tabs on your health at a glance. Lightweight oxygen meter is designed for non-medical periodic spot checks of pulse rate and blood oxygen saturation levels. Color changing backlight indicates green for normal, yellow for caution, red for alert. Finger oximeter is portable and non-invasive.Large numbers are easy to read.Includes carrying case and 16" lanyard.Ideal for home and travel.Requires 2 AAA batteries (not included).2 1/2"L x 1 1/2"W x 1 1/4"H.Not intended for diagnosis, treatment or to replace a doctor visit. 2 1/2"L x 1 1/2"W x 1 1/4"H Includes carrying case and 16" lanyard Measures pulse rate and blood oxygen saturation levels Large numbers are easy to read Portable and non-invasive design