These 3 per side Kluson tuners were used on all Gibson electric guitars from 1964 - 1969.

A Breif Gibson Tuner History:

"Ring" means the plastic ring at the bottom of the tulip

"Line" Means "Kluson Deluxe" stamped on the back of the tuner

1947 - Early 1952 :    Single Ring, No Line

1952 - Mid 1956 :      Single Ring, No Line

Mid 1956 - Mid 1960: Single Ring, Single Line

Mid 1960 - 1963 :       Double Ring, Single Line

1964 - 1969 :             Double Ring, Double Line