i think it is midge braid, by hairline i believe .just my version of the humbug,a little tougher than chenille as you can wind it real tight.one of those slow sinking,tumbling type of flies.i tie in the black then the charteuse and tie off at mid hook and double wrap the charteuse ti build it up and give it a more spidery look.pull the black over real tight add the legs then wrap once or so with the black for the head.good fly for the beds