The Sof Comfort All Shoe Comfort Insole is an upgrade to the standard sock liner in your shoe. Its slim design increases comfort and helps absorb shock while controlling perspiration. May be trimmed as needed for a true custom fit. To trim simply remove the existing insole from your shoe line it up with your new insole as a guide and trace with a ballpoint pen. Carefully cut with a sharp pair of scissors then insert into your shoe with the top side up.