A nicely designed winder makes everything easier, especially when you'd rather be flying than fussing with string. Prism couldn't find one on the market that they liked so they designed their own. It's molded from unbreakable polycarbonate with just the right angles for smooth unwinding, and a nice shock cord keeper that snugly controls all the loose ends. Fits easily in your pocket with three cool colors you can use for different lengths and strengths.