Based in Yorkshire we often find lots of Rhyac nymphs where we fish with the prevalence of Green Sedges around us. This s a regular fly imitation that we fish and czech nymph with. The Semperfli team developed a good Rhyac wool to make tying the Rhyacophila nymphs easy, with this superb wool. As you can see from the pictures it matches the Ryhac we have found when kick sampling Yorkshire Rivers. Simply wind around the hook, add a clear shellback and cover the head with black permanent marker pen. For an even better imitation add Semperfli Straggle String ss-SF7300FL at the head which with its UV flecks adds stunning legs..