Rubber horn bulb (black rubber) , approx. diameter 93mm with 16mm dia. hole. brass ferrule.
this rubber horn bulb can have the open end opened out if too small using a rough round file. it has a removable plug in small end. to fit - remove brass end ferrule and push on to the horn tube, remove the end bung and push this on to the tube (easing with wash up liquid helps), then push the round bulb on to this (locates into a moulded ring) - then pull the brass ferrule back into place over both parts of rubber bulb - the part should fit snugly.