A Crease Marker, also known as a Hera Marker, is a hard plastic tool with a rounded edge that can be used to mark a crease line on your fabric when fabric pens aren't suitable. Popular with quilters, the fine, rounded edge makes it easy to mark quilt lines (straight or curved) onto your fabric before sewing. The creases don't fade like some fabric markers do, so no need to worry about rushing to get your project done before the marks disappear.
Can also be used for scrapbooking, cardmaking, and other paper craft for creasing and folding cardstock.