These Stinger four sided 15mm x 15mm x 2.5mm carbide knives are used on many brands of carbide helical cutter heads like certain Stinger and laguna Sheartech and others. These knives are used with a flat head screw CWI-T20-2 to hold them in place. Stinger also has screws and knives available for HELICAL HEADS with tapered head step down screws CWI-T20-1 and carbide knives CWI-HC-I1 like used on Byrd and Stinger helical heads. The price on these knives are per knife but are usually sold in sets of 10 per order.

It is also possible to change the style of carbide knife in certain carbide helical heads from a 15mm x 15mm x 2.5mm flat head knife and screw to a tapered head knife and screw as long as the screw size in the cutterhead is the same. Both the knife and screw must be changed to match.