Not sure if this helps or not .I have a mail pouch thermometer that looks almost the same as yours ,except mine is a darker blue the back is lime green the temp goes up to 120 degrees the thermometer is 13 inches long . There is no makers mark only the numbers 123 at the bottom of the thermometer tube. I bought it at a local antique shop, I could tell it had been outside for some time, so I assumed it was real. But I am no expert ! OH and mine is solid wood on back that is 16 inches long.
Last edited by Tunk-Z28; Sun Apr 15 2018 11:54 AM. Reason: mistake