This Stinger 5 Row carbide helical cutterhead is made for use on Casadei PFS41 and Minimax FS41 Classic 16" Planer/JointersStinger carbide helical cutterheads are designed by CWI Woodworking Technologies to be the best performing cutters on the market today for thickness planers and jointers. Helical technology for improved performance on thickness planers and jointers has evolved over the last number of years to the point today where almost all users realize the vast difference over standard high speed steel heads as well as the hybrid quick change high speed steel heads.In normal cutting conditions it is well proven that a carbide wood cutting tool edge will outlast high speed steel by as much as 50 times the life span. With the Stinger 15mm square four sided carbide knife users will see up to 200 times the lifespan of a typical sharp high speed steel knife. Our customers find they get between one to two years of life for each edge of knife cutting hardwoods like oak and maple so typically users will see up to eight years of normal use of their planer or jointer before having to replace their worn knives.What Makes the Stinger Different?Typical helical carbide heads on the market today use four to six rows of knives. The Stinger uses FIVE rows!Why?For the best results when planning wood with a helical cutterhead the user wants more knife cuts per inch as the wood feeds through the machine but as well because of the stagger of the knives the head needs to have very good overlap of knife placement to avoid knife marks in the wood. Tests show a five row head will provide more knife cuts per inch in the cut and therefore a finer finish than a four row head. A six row head you would think then is better again but test results don’t show that there is any vast improvement. But here is the difference: The Stinger FIVE row head provides five separate positions of each knife for superior overlap than both the four row and typical six row. Most six row heads sold for smaller woodworking machines are actually two rows of three knife placements meaning even less overlap of knife than a four row.The Stinger FIVE row head uses a 15mm square four sided knife that is specially designed with a convex edge to increase the shear action of the knife for better cut in difficult woods. But even better the knives are then placed in the head on a three degree sheer angle to enhance the quality of cut even more. Tear out on most hardwoods and softwoods is virtually nonexistent.Carbide helical cutterheads are well proven to be far superior to high speed steel knife heads for ease of maintenance, quality of cut, lifespan of the knives, and not to be forgotten is the major improvement in quietness in the cut. The Stinger Five Row Carbide Helical cuttterhead for thickness planers and jointers are truly in a class of their own.