Here is one of the Brother cast on combs, I am using it on my SK155 to do a live cast on, this would be for waste yarn as it will unravel if the comb was taken off after starting.
by livelefthanded
by The Crochet Crowd
by Fiona Morris Designs
by brotherdrumcarder
by The Chilly Dog
by Knitting with Suzanne Bryan
by PleasantSeas