Diagnostix 2100 Digital fingertip pulse oximeter. Reads SP02 and pulse rate. Accuracy: SP02 Sp02 +/-2%/HR +/- 5 BPM. 3-color OLED display, 6 changeable display modes. 10 display brightness settings. Complete with carry lanyard, black bumper and 2 “AAA” batteries. 2 year limited warranty.