The salad spinner is a midge pupa fly, and it has an interesting history. I recommend reviewing my posts of 12/17/2019 and 12/12/2015. The 2019 post contains a materials table, and the 2015 post provides the tying steps. I have experienced reasonable success with this unconventional fly, and it is often my first choice when I see a plentiful amount of midge adults buzzing about near the stream. I am not a trout, but I love the fine red wire rib and the emerging antron wing.
My shrinkage of this fly was not very significant, so I tied four additions, and I gave a couple to my fly fishing friend. Midge season lasts all year, so I could knot one of these on my line in the not too distant future.