Our Ferrule and Guitar Jack Tightener offers a quick & easy way to tighten a loose jack plug on any surface-mounted input! A must-have for guitar luthiers!
The guitar jack tightener is designed to friction-lock from the inside of the receiver. It also works great for removing 1/4" string ferrules.
Insert the guitar jack tool into the jack, then use an allen wrench (as shown) to tighten the internal set screw. This gives the holding power needed to tighten the retainer nut, without having to go inside of the instrument.
Here's a demonstration video put together by Dave's Guitar Shop:
https://www.youtube.com/watch?v=_Vu0NmU8k5E
Specifications:

Installation Instructions:
For the holding power that you need to install and remove 1/4" guitar jacks, tuner, and string ferrules. Insert the male end of the tool into jack or ferrule. Insert 5/64" allen wrench into set screw, and turn clockwise to tighten, expanding prongs for as much holding pressure as needed. (Use with caution when using in plastic jacks.) Do not tighten set screw when not in use. This could cause permanent damage to the tool.