Write on any dry erase surface and wipe off easily with microfiber towels cleans better than standard whiteboard erasers. Each set includes 5 dry erase pens and 5 soft towels. Towels measure 4-1/2" x 4-1/2". Sold as 3 sets for a total of 15 pens and 15 towels. Handy whiteboard sets for your classroom. total of 15 pens and 15 towels.Details:Black4.1/2" x 4.1/2".Sold as 3 sets 5 each15 pens and 15 towels of 30