AN IMPORTANT NOTE: This tool and its accessories are designed for use with Woodland Scenics own high-density, nontoxic expanded polystyrene foam. Since many foam products emit a toxic gas when heated, this tool should never be used with ordinary Styrofoam, foam rubber or other foam products. Designed especially for cutting thicker pieces of foam, this versatile knife comes with a replaceable 3" (2-1/4" long cutting surface) blade. Ideal for cutting and carving foam sections as you shape your scenery. (Replacement blades are available separately as #785-1434.)