It will consist of metallic cone with half angle of 15′ -30 ±15′ and 30.50mm coned length. It will be fixed at the end of a metallic rod with a disc at the top of the rod so as to have a total sliding weight of 148± 0.5 gms. The total rod shall pass through two guides. (to ensure vertical movement) fixed to a stand. Suitable provision will be made for clamping the vertical rod at any desired height above the surface of the paste in the trough. A brass trough 50 mm internal diameter and 50 mm depth will be provided as per IS specification resting on M.S.bars.