Catgut Biothread by Frostfly

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  • Regular price $3.39
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  • One of the best materials for tying killer, super-realistic nymphs.
  • Unique and versatile – a top choice material among world’s most experienced fly tyers.
  • It is opaque, solid-colored when dry and becomes milky translucent and shiny when wet.
  • When submerged in water, it becomes very soft, flexible and stretchable, which makes it super easy to work with.
  • As it soaks in water, its volume also increases, giving a plump appearance to the fly.
  • The most amazing benefit of using this material is the way it looks in water – flies tied with it look extremely authentic, have lifelike texture and super-high shine.
  • The material has been treated to extend its durability under water.
  • To apply, soak the part you want to use in warm water for 3-5 minutes prior to tying. The color will change from opaque to more milky and transparent and the material will be super-flexible and easy to wrap.
  • When the fly dries, the body will go back to its solid-colored state.
  • By using various colored threads underneath it for underbody, different effects can be achieved as the color peaks through the wet material.
  • About 50 cm long (about 20”), comes in four diameters and wide range of colors.
  • Sizes (Diameters) and hook recommendations:
    • Extra Small (0.18mm) – for hooks #16 and #20
    • Small (0.3mm) – for hooks #14 and #16
    • Medium (0.5mm) – for hooks #12 and #14
    • Large (0.7mm) – for hooks #8 and #10
  • Absolutely perfect for making bodies for nymphs and emerger flies.
  • Also a great choice material for making loops on traditional salmon flies (small diameters in particular, XS and S)