UV-curing resins with multiple functions, all while curing in secondsUV resins allow for infinite work time but cure within seconds when exposed to one of Loon's UV lights. The result: a perfect application with a durable, clean, and glossy finish. The three different viscosities were developed to perform in three different circumstances:UV Flow is the same viscosity as water and locks in threads as a head cement and provides a super-thin coating to heads, bodies or midges.UV Thin is viscous enough to build heads or wing cases, but thin enough to coat bodies on small, low-profile flies.UV Thick is perfect for building big heads, bodies, and wing cases. -UV Blocking application needles-Taper-Tip needle prevents clogs-Build fly heads and bodies-Instantly cures with sunlight or UV light-Brush applicator included-Needle tip included for precision tying-Available in 1/2 oz and 2 oz