Liquid crystal thermometer with a peel-off adhesive back, 36°-78° F range, 2° increments. Stick it on the side of a carboy or bucket to monitor fermentation temperature; lasts forever. Strong adhesive will not peel off or get damaged, so be sure to purchase one for each fermenting bucket/carboy you plan on using.
Please Note: Once stuck onto the side of your vessel it should be left in place. Trying to attach it after removing it can result in the adhesive backing not sticking.