The new Mozart trimmer is designed to be quick and easy to use & comes complete with full instructions. The weld or joint seam is trimmed in two stages. During the precut the spacer claw is swung in place below the blade so that , as the cut is performed, a residual seam remains. For the subsequent trimming cut, swing the spacer claw 90 degrees to the side and trim the seam flush with the material. This is a very well made German tool for the trimming of vinyl floor weld. Spare blades come in a dispenser packs of 5.