Air Flow Anemometer Handheld LCD Digital 45m/s Wind Speed Meter air Flow Thermometer Mesurement Gauge USB Interface 8902BZ

I bought this unit in Nov 2014 from Amazon and used it for a couple of times. Less than four years later, I wanted to use it again and found it RIP. No response at all to four fresh AAA 1.5v batteries. The unit was stored in a cool, dry place and without the batteries inside. Everything, including the package inside and outside, looked precisely the same as the posting. While the posting shows manufacturer as Shenzhen Wave etc., my unit shows nothing; however, it is safe to assume a product from Shenzhen. In 2014, I paid $55. Now it is selling at $156. What gives?