Sun Company Frig-o-gage - Cooler-Refrigerator-Freezer Thermometer | Refrigerate and Freeze Zones | For RVs and Motor Homes VISIBLE SAFE ZONES - Frig-o-gage shows safe "REFRIGERATE" and "FREEZE" zones to ensure your fridge or freezer is at the correct temperature. EASY INSTALLATION - Features an adjustable, easy stick-on bracket.