This fibre is identical to PULSE but has additional uv fibres.  This 20mm version is the smaller sibling of Pulse and in our developmental phase did much work on the size and density of the uv additive.     During development different ratios and sizes of uv were trialled and we have settled with just enough uv fibres to ensure that the movement is not inhibited and just gives a hint of sparkle, not overpowering the product.  It will undoubtedly be a welcome addition to the flyfishers armoury.