TCT cutting edges. Strong, hardened steel shanks. Twin fluted for smooth finish. For biscuit joints, slots and grooves. Max 12,000rpm. Use 13mm bearing for No. 20 biscuits and 19mm bearing for No.10 biscuits. TCT cutting edges. Strong, hardened steel shanks. Twin fluted for smooth finish. For biscuit joints, slots and grooves. Max 12,000rpm. Use 13mm bearing for No. 20 biscuits and 19mm bearing for No.10 biscuits.