Parallelogram milling inserts have an offset rectangle shape with four sides and two acute (less than 90°) cutting points at opposite corners. They mount to a compatible toolholder, which attaches to a milling machine. These indexable inserts 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. Parallelogram milling inserts are differentiated by their nose angle measurements. Narrow cutting-point nose angles provide small cutting depths and decreased vibration while wide cutting-point nose angles provide large cutting depths and increased cutting force. 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.