CrazyMill Cool Ball with four teeth is available in five versions and in the diameter range of 1 to 8 mm (.039“ to .315“, fractional inches available): a short version (Type A) for maximum milling depth of up to 2 x d, a medium one (Type B) up to 3 x d and a long one (Type C) up to 5 x d; the cutting length of these versions is 2 x d. Additionally two more versions are available with a progressive flute-angle: one version for a maximum milling depth of up to 3.5 x d (Type M) and one for a maximum depth of up to 4.5 x d (Type N), in these cases the cutting length is corresponding to the respective milling depth.