A hard layer of wax applied with a low iron temp to condition the base for use with hard waxes. Our hardening wax scrapes off like a green wax and then the skis are ready to use with racing waxes and higher iron temps. This process minimizes the risk of burning new base material and increases out-of-the-box speed for all skis. We highly recommend hardening skis after stonegrinding to recondition the base material and get the most durability and speed out of your future wax applications.