These blades fit all of Accu products except Shear Sharp. For the best possible sharpening edge, we only use the finest American-made diamond honed tungsten carbide available. The result is the finest line of carbide sharpeners on the market today, at any price. These blades are reversible for double life and most users report an average life of 5 to 10 years between replacements. Beware of other brands that use cheap imported carbide!