Loon(TM) - UV Knot Sense A UV-curing coating for knots. With UV Knot Sense you can smooth and strengthen your newly tied knots immediately. After application, it Dry Flies instantly with Loon&&';;s UV Nano Light, UV Bench Light or with direct sunlight. Also works great for repairing damaged flies and completing household projects. Ideal for coating knots for strength Smoothes knots to easily slide through guides Cures soft and pliable Instantly cures with sunlight or UV light Quickly repairs damaged flies 1/2 oz