Trade Secret Fill Stick black. This black-color professional fill stick is blended from high-grade wax, not putty, that does not shrink once the repair is completed. The high grade blend of pigmented wax used in the making of Trade Secret Fill Sticks ensures that you get the finest results when repairing nicks, gouges, scratches and other defects on furniture, cabinets, floors and woodwork. The repair sticks contour to the shape of any defect. Simply fill in the defect and remove the excess with a cloth. This product can also be used on Formica or plastic surfaces.