Finger-Tip-Pulse-Oximeter-RVFM-3903-This-Pulse-Oximeter-can-be-used-to-measure-human-Haemoglobin-Saturation-&-Heart-Rate-through-your-fingertip-The-meter-uses-a-light-emitter-with-red-&-infrared-LED-that-shines-through-a-reasonably-translucent-part-of-your-body-that-has-a-good-blood-flow-e-g-your-fingertip-Opposite-the-emitter-is-a-photo-detector-that-receives-the-light-passing-through-the-measuring-site-The-Oximeter-is-easy-to-operate-simply-put-your-finger-into-the-rubber-cushion