Slim Waterproof Silicon Slit fly boxes are super tough, and easily slide into the pocket of a vest, sling or fishing shirt. The self healing silicon means the box will not get worn out like standard foam.
Two sizes of the Slim Silicon Fly Box listed here. The Medium is 5.33 x 3.75 x .60 inches and the Large is 7.33 x 3.75 x .60.