Scholl Velvet Smooth Extra Coarse Replacement Roller Heads Scholl Velvet Smooth Extra Coarse Replacement Roller Heads are designed to fit the Scholl Velvet Smooth Express Pedi with Diamond Crystals for beautifully soft feet in an instant. The extra coarse roller heads are perfect for rapidly removing very hard, stubborn skin before using the soft touch roller head for a smoothing finishing touch.