Knowing your coolant temperature can help to prevent burn injuries. Thermo Cap, with its built-in calibrated thermometer, indicates the coolant temperature. This is useful information prior to cap removal. Never attempt to remove Thermo Cap when the coolant temperature is very hot. The escaping hot coolant and steam may burn you. Check the Thermo Cap temperature indicator to determine if the coolant is cool enough to make removing Thermo Cap safe. If the coolant is very hot, then thoroughly rinse the radiator with cool water, until the coolant temperature drops into a cooler safe zone Thermo Cap's integrated coolant reclamation valve works great with your coolant recovery system. Your radiator can reclaim coolant from your overflow bottle. Wide 30 degree to 270 degree Fahrenheit temperature range. Calibrated in centigrade and Fahrenheit. Color-coded temperature ranges. Chromed crown with a colored trim ring. Indicates coolant temperature, Helps to prevent coolant injuries, integrated coolant reclamation valve, Improves under hood appearance, Fits most domestic or import vehicles and various valve pressures available.