What Is Hatching? Do You Have The Right Fly? Matching The Hatch Is The Essence Of Fly Fishing. The Guideline Caddis Fly Shows That You Are Serious About It. The Graphite Grey Cap Is Made Of 100% Brushed Cotton Twill With Velcro Closure In The Back. Whereas the Rifle/Stone & Tangerine are made of 47% brushed cotton twill, 25% polyester and 28% nylon. Velcro closure in the back. One size fits most.