Digital Fingertip Pulse Oximeter A portable finger tip pulse oximeter ideally suited for home, sport, or aviation use. Reads SPO2 and Pulse Rate Accuracy: SPO2 2% / HR 5%BPM 2 changeable display modes Bright red LED display Fits fingers with a thickness of .3" to .8" (6.6mm to 19.7mm) Carry Lanyard 2 “AAA" Batteries Instruction Booklet 1 yr. Limited Warranty