This Draper Combustion Gas Detector Kit is ideal for determining if CO&sup 2; is present in a vehicles cooling system. CO&sup 2; in the cooling system can indicate a head gasket leak, cracked block or a warped head, etc. Simple to operate by adding blue detector fluid to the tester & placing tester onto the radiator; air is drawn through the liquid which will change colour to yellow if CO&sup 2; is present. Supplied with detector fluid.