Firefly is a proprietary material that provides 8-10 hours of glow from 30 minutes of direct sunlight. The bright-colored resin makes it highly visible in dim or dark lighting. Dan said that having chunks suspended in the handle increases the surface area of the glow material (revolutionary in that all others, only the outside surface glows). Also, light passing in and out gives greater perceived glow. Firefly is very resistant to the elements as everyday use items. Small pieces that have been drilled out are being tested as hammock attachments to help see the lines in the dark or as zipper pulls for a backpack or pouch. Dan mentioned that they would make handy trail markers, as well.