OxyCheck Pulse Ox: $199 on Finger Tip

OxyCheck obtains results in less than 10 seconds. OxyCheck reliably turns on with finger insertion and turns off with finger removal. No need to worry about draining the batteries due to failure to turn off. Works on pediatric to large adult fingers
8mm to 26mm (0.3-1.0 inch) thickness. Uses standard, inexpensive, easy to find AAA batteries. 18 hours of continuous use or 1600 spot-checks.

More information on OxyCheck is here