The Pop Up disposable cooking thermometer, also known as the Pop Up timer, is the most accurate temperature indicator of its type in the world. The Pop Up disposable cooking thermometer, also known as the Pop Up timer, is the most accurate temperature indicator of its type in the world. Using patented organic firing mediums, the Pop Up accurately indicates (within plus/ 2°F) when poultry, meat and fish items have reached their optimum level of doneness, thus eliminating the guesswork and assuring a perfectly cooked product each and every time. Volk Enterprises has a Pop Up to fit just about any type of food item, with products ranging in temperature from 138°F to 203°F.