B129B‡ Metal Index
ThunderBit® Metric High-Speed Steel, 135° Split Point
DBTBM1‡ 1 41 (1.61)
DBTBM1.5‡ 1.5 48 (1.89)
DBTBM2‡ 2 51 (2.01)
DBTBM2.5‡ 2.5 60 (2.36)
DBTBM3‡ 3 70 (2.76)
DBTBM3.5‡ 3.5 73 (2.87)
DBTBM4‡ 4 83 (3.27)
DBTBM4.5‡ 4.5 86 (3.39)
DBTBM5‡ 5 92 (3.62)
DBTBM5.5‡ 5.5 95 (3.74)
DBTBM6‡ 6 102 (4.02)
DBTBM6.5‡ 6.5 105 (4.13)
DBTBM7‡ 7 105 (4.13)
DBTBM7.5‡ 7.5 111 (4.37)
DBTBM8‡ 8 114 (4.49)
DBTBM8.5‡ 8.5 121 (4.76)
DBTBM9‡ 9 124 (4.88)
DBTBM9.5‡ 9.5 127 (5)
DBTBM10‡ 10 130 (5.12)
DBTBM10.5‡ 10.5 133 (5.24)
DBTBM11‡ 11 140 (5.51)
DBTBM12‡ 12 149 (5.87)
DBTBM12.5‡ 12.5 152 (5.98)
DBTBM13‡ 13 152 (5.98)