3 Style Saw Bits will fit only a 3 Style shank "Single Circle" design. The large gullet of 3 Style shanks are well suited low powered mills processing relatively large logs at moderate feed speeds. A saw with the maximum number of teeth permits the fasting possible carriage speed, resulting in maximum production from the saw. Regular and Long type bits can be used with Regular, Wintar style shanks. Many sawyers find the long type bit does not run as smooth as a Regular type bit until after is has been sharpened a few times. This owes to the longer swage taking a larger bite while it is new.