Final setting time needle shall be of the same section as needle of initial setting time shall is 30 ± 1 mm length and fitted with a brass attachment hollowed out so as to leave a circular cutting edge 5 ± 0.1 mm in diameter. The depth hollowed out shall be 0.5 ± 0.1 mm. A 0.75 mm diameter vent hole shall be provided. The needle shall project 0.5 ± 0.1 mm beyond the cutting edge.