The prior comment is correct in that the spiral head does not fit on the smaller KA's. I actually was determined to try the spiral head on my small KA, and cut the end off with an angle grinder until it just cleared the bottom. I actually had to shave a little off the sides of the hook as well, since it brushed the sides of the bowl as it turned without doing so. The result works pretty well, and is much much better than that standard C hook. I am dismayed that a company like KA, with a mixer that has such a large market share, took so long to produce a dough hook that actually works like intended. The C hook, in my use, was nearly worthless.