D420 shell end mill bore cutters have standard bore sizes suitable for standard shell mill holders. They can be used for slitting and cutting in steels, stainless steels, aluminium and cast iron and are made from High Speed cobalt to give you great wear resistance coupled with excellent tool strength and performance. They have a titanium carbo nitride coating which promotes longer cutter life and also improves performance when milling hard and abrasive materials. D420 shell end mill bore cutters come in a large range of sizes, with diameters up to 100 mm available.