Specification: For determining the hardness number of Mastic Asphalt for flooring. It consist of an internally insulated cabinet to the base of which is fitted a water bath having two taps. The bath is heated by an immersion heater and the temperature is controlled with the thermostat at 35 ° +/- 0.5° C. A 6.5mm dia pin is loaded on the specimen by means of a lever to give a 31.7 Kg weight. A dial gauge 0.01 x 25 mm is provided to record the penetration of pin into the specimen.