Gotoh adapter bushings are intended for use in converting a modern 10mm drilled headstock to accept Gotoh SD90 and SD91 series tuning machines with standard non-locking posts or traditional magnum lock posts (MG-T). These bushings are not suitable for Gotoh's standard Magnum locks posts (MG) that lock without rear wheel locking mechanism, or HAP and HAPM post options.
If you are using a set of genuine Kluson tuners on a guitar with larger headstock holes, please see MB65N-L US bushings here.
Outer diameter: 10.2mm, 6.5mm inner diameter. Sold as a set of 6, nickel, gold or aged nickel finish.