Used to determine grade of bitumen. The penetration tests determine consistency of bitumen for the purpose of grading. Depth in units 1/10 of millimeter to which a standard needle having a standard weight will penetrate vertically in a duration of five seconds at a temperature of 25°C determines penetration for gradation. but the unit is compact with timer to control duration of penetration. The instrument is provided with lead screw gear arrangement, Leveling screws, Spirit level. but the unit is compact with timer to control duration of penetration. The instrument is provided with lead screw gear arrangement, Leveling screws, Spirit level.