The Holographic Silver Diawl Bach is a fly of Welsh origins that began life as a River pattern but which has become one of our most well known and appreciated Stillwater patterns for all Trout species. Whether fished in smaller or larger sizes, the pattern is representative of many food types of the Trout diet, and is not limited in any way as to where it will fish, being as popular on the large Stillwater reservoirs as the small traditional Loughs of northern Scotland or Ireland.