Hey Thom. I am glad to explain, which is easier over the phone, than via e-mail. The horn button is a friction-fit into the cup, via a rubber grommet. Additionally, on the standard horn button, there is a spring steel disk, that sits in the bottom of the steering wheel, followed by the buttom cup, then the three-hole bolt circle plastic spacer and finally the horn button. Let me know if I can help you with any additional information.