Prolong the life of your pencils with these handy extenders. The silver one fits larger Derwent diameter pencils (up to 9mm) such as Inktense and Artists, while the black one fits all other standard size Derwent pencils (up to 7mm in diameter) such as Graphic and Watercolour. Set contains one of each size. Details:2 pencil extendersFeatures a metal screw-style collar that holds pencils more firmly than a standard clutch style extenderHollow design allows for use as a holder or protector for longer pencils