Finger Pulse Oximeter -Blood Oxygen Saturation - Athletic and Aviation Pulse Oximeters, Respiratory Rate, PI Sleep Monitor， Batteries and Lanyard (Respiratory Monitor - Silver + Black)

Was working fine the first set of batteries, when I replaced them now it won't turn on, These are new batteries, so no its is not the batteries are old, even replaced them with more new ones and still doesn't turn on. Very disappointed with this item.

Works great