Clover Fabric Folding Pen Think of a felt tip pen that is filled with what amounts to be a very unique fabric softener. Just remove the cap and with the felt tip trace either a straight or curved wet bead line on your fabric. The fluid from the pen causes the fabric fibers to relax at the point of application. Now you can fold along that specific line with ease and either finger press or iron to form a sharp, lasting edge. The pieces of your project can now be assembled easily and precisely and they will look great!