Convert your Cameo 4 into a sketching and drawing machine by using the Pen Holder tool. The Pen Holder allows you to use a range of pens, from a thinner standard ball-point pen to a thicker felt-tip marker. Details: 0.25" - 0.4" (6.35mm - 10.16mm) diameter range For use with the Silhouette Cameo 4 machine Contents: 1 pen holder 3 threaded adapters