Gotoh TLB-1C String Ferrules - Set of 6 - Chrome

String ferrules (also called bushes) are fitted into holes drilled in the back of an electric guitar. The ferrules should line up with the holes for the strings in the bridge. A smaller hole of around 3mm is used to connect the string ferrules with the bridge.

Using top mounted string ferrules along with rear mounted ferrules is a nice option for a custom guitar. This is used as a replacement for a stop bar or tailpiece. It gives the illusion that the strings are coming straight out of the body of the guitar.