Neco Headset Expander Top Cap Star Nut Plug Bolt Stem Expanding Nut Bolt Carbon Fiber Cap Cover Long Large Size (Small Aluminum Cap 1 inch)

Easy to install with a good grip.

This neco small 1" compression cap fits great inside my 1" steerer tube carbon fork. I don't think you need to waste extra $ for the carbon cap since I purchased the aluminum cap but just ended up using my old colorful cap since I really didn't want the words "neco" on my steerer top. Works great. No more needing to find/pay someone to pound in that star nut. Easy DIY.

No instructions, but saw on a website that the outer part is tightened in place with a 6 mm hex then it can be used similar to a star nut with the supplied 5mm bolt. Works like it should.