Bitumen penetration grade 40/50 bitumen means the penetration value is in the range 40 to 50 at standard test conditions which commonly used as a Paving Grade. Bitumen is applicable for the production of hot mix asphalt for bases and pavements and for road construction. Penetration Grade Bitumen supplied by RABIT (RAHA BITUMEN) Co. This bitumen is produced through aeration on vacuum bottom (the raw material used for making bitumen left in vacuum distillation column in oil refineries) in bitumen production units. Its penetration grade ( the measure of bitumen hardness) is between 40 to 50. Bitumen is specified by the penetration and softening point test. Designing is by penetration range only. The penetration grade bitumen has a thermoplastic property which causes the material to soften at high temperatures and to harden at lower temperatures. This unique temperature-viscosity relationship is important when determining the performance parameters such as the adhesion, rheology, durability and application temperatures of bitumen.