A little help

Main Train Horns
1

I just got a k3 mount and I have bells 2 and 4h on it. What do you all have screwed into the bottom? It’s just one big hole and any ideas with pictures would help thanks

2

Do you mean the stock K3 manifold? If so its 1/2" NPT female at the base.
If you’re talking about a different mount, post a pic if you can

3

^^ What DBO said.

…and I guess you have a block off plate in place of the #1 bell?