The HM90 ADCT 1505 insert from Iscar features an asymmetric shape with different helix angles on the two cutting edges to reduce chatter and vibration. The edges are colored gold and black, and are intended to be mounted alternately to create a variable helix configuration. This feature is said to improve performance in shoulder milling by reducing vibrations. The inserts are well-suited for less rigid setups, long-overhang applications and thin-walled workpieces, among others. They can be used with Iscar’s Heli-Mil family of milling cutters.