Review on Polder 510 Glass Candy Thermometer by Michael Fairfield

This worked for a few batches of yoghurt (185F) but when I was making toffee (290F) I found that once it had cooled the glass tip was so thin that it cracked. I don't know if the broken glass hit the toffee, but I didn't risk it; Both the thermometer and the toffee ended up in the bin. Also, I didn't like the display; with degrees marked with digits only every 50, and lines for every 5 degrees in between. The thermometer I used for 20 years had digits every 10 degrees and dashes every 2 degrees; technology behind it?