I used the dial type and calibrated them before putting them in.
There is a square or hex just under the dial part on top of the stem. Take a glass of crushed ice and a little water and put the thermometer in that. when the needle stops dropping you can grasp the hex gently with pliers and hold steady and then rotate the dial to 32 deg.
There is a square or hex just under the dial part on top of the stem. Take a glass of crushed ice and a little water and put the thermometer in that. when the needle stops dropping you can grasp the hex gently with pliers and hold steady and then rotate the dial to 32 deg.