Many experts consider Zap-A-Gap indispensable for fly-tying. It forms a solid bond and fills gaps. Besides using it for your knots, Zap-A-Gap is great for gluing on eyes, locking dumbbell eyes in place, etc. It's great for reinforcing your leader-to-line connection knots, and handy for emergency gear repairs along the stream. This package comes with the brush-on applicator that a lot of tyers swear by.
MFG# ZF13