Square (S) milling inserts have four sides of equal length that form four cutting points with 90° nose angles. They have strong cutting edges for face milling, heavy-duty roughing, and turn milling applications. These indexable inserts mount to a compatible toolholder, which attaches to a milling machine. They can be rotated (indexed) to expose a fresh cutting edge when the old one dulls. They can be replaced with new inserts of the same type or different types without removing the toolholder from the machine. Indexable milling tools require fewer tool changes than solid tools in high-volume metalworking and fabrication applications with high speeds, high feeds, and difficult-to-machine materials.