DCGX 21.51 LH Carbide Insert- XC899 ~ ISO insert number is DCGX070204-LH. ~ I.C. is 1/4". ~ L is .307. ~ S is 3/32". ~ d is .110. ~ r is .016. ~ LH Chip-Breaker is more suitable for machining aluminum alloy with larger cutting depth and higher feed rate.