The triangular ceramic replacement blades (item #50264). 

NOTE: Only one piece is included. Two pieces are shown in photo. You must order a quantity of two. 

Replacement Instructions: Remove the Phillips head screw(s) and cover over the blades. Save for re-assembly. Remove the existing carbide blades and discard. Insert new carbide blades with sharp edge of grind facing into v-slot. This applies on both sides. Replace the cover and Phillips head screw(s). Tighten screw(s).