Designed with spiral flutes and various lengths and forms to give high quality centre holes. • TiN Tipped • 60° inclusive angle. • Manufactured to BS 328 : Part 2 : 1986, DIN 333A, ISO 866, ISO 2540, ISO 2541. • Metric Sizes: 4.00, 6.00, 8.00, 10.00 and 12.00mm. • Imperial Sizes: BS1, BS2, BS3, BS4 and BS5.