Slow and steady temperature monitoring ensures the best, juiciest results and this thermometer is safe to be left in the oven or grill during use. The temperature gauge rests at the bottom of the dial (room temperature) and slowly rotates clockwise as the temperature in the protein increases during cooking. CONVENIENT: The 2″ dial features USDA meat temperatures for quick reference. VERSATILE DESIGN: This product is made with a durable, tempered glass lens. The material is safe to leave in the oven or grill during cooking.