Klinkhammer

The Klinkhåmer Special (commonly spelled Klinkhammer) is one of the most successful and revolutionary emerger patterns in modern fly fishing. Devised to mimic a caddisfly or mayfly struggling to break through the water's surface film, its history is a fascinating mix of careful observation, collaborative naming, and parallel evolution in fly design. 

The fly was created in 1984 or 1985 by Dutch angler Hans van Klinken while he was fishing for grayling and trout in central Norway, specifically around rivers like the Glomma.