Grizzly H7764 Byrd Tool 6-Inch Shelix Cutterhead Made in the USA by Byrd, these indexable carbide insert cutterheads are very well made and leave a great finish The inserts are positioned along a spiral pattern and rotate at a slight angle for a shearing action that leaves a glassy smooth cut on the toughest Comes with all 30 inserts on the cutterhead, plus 5 extras