The blades in this range are available in a choice of 4 different grades of material: Standard Toolsteel - Well Approved for Universal use High Carbon, High Chrome - Harder Wearing Toolsteel High Speed Steel - 18% Tungsten Carbide (approx 400% higher cutting yield) Solid Tungsten Carbide Tipped for the Ultimate cutting edge. Models available are: A78Z, A80Y, A80Z, A106, A132, A152, A25/35X, A25/35S, A30/42VH, A30/42H