What+is+the+difference+between+the+AR-816+and+HP816A

What is the difference between AR-816 and HP816A Handheld Wind Meters?

 * 1) These wind meters are almost identical in functionality.
 * 2) The HP816A has a button on the front of the unit to switch between degF and degC. The AR-816 has a pinhole on the back.
 * 3) The HP816A is slightly larger and fits better in your hand (opinion).

Considering these two factors, we prefer the HP816A.