Every time someone messes up an expensive full carbon fork by whacking a steel start nut inside the steerer, a dozen kittens die. Please don't kill kittens.

FSA Compressor plugs are proper complete top assemblies for carbon steerers to replace the traditional top cap/star nut assembly. Includes integrated cap, bolt, and expander.

The 1 1/8" size fits carbon steerer tubes with an inner diameter of 21mm to 26mm, and 1" fits most 1" threadless carbon forks.