These Rubi Tools Porcelain Wheeled Tile Nippers (83942) are specially designed for cutting narrow strips of tile up to a maximum of 7/16" (1 cm.) in thickness. These tile nippers are equipped with tungsten carbide scoring wheels and feature a titanium surface treatment for long life. With a gentle turn， the scoring wheels can be repositioned as they wear. If totally worn， they can be replaced with the 3/4" (18mm) GOLD Spare Scoring wheel 01953.