This complete Kluson set of 3 per side tuning machines is available with oval or keystone buttons and a high quality gold or nickel plating with an improved 15:1 gear ratio for more stable and accurate tuning. The housing and button type are period correct for a variety of production dates. This set comes complete with both bass and treble side tuning machines, 8.8mm O.D. vintage bushings with 1/4 inch I.D. and mounting screws needed for installation.[SKU:KD-3-GM]Specifications:¥ Gear ratio= 15:1¥ String Post length= 1 inch¥ String Post Diameter= 1/4 inch¥ Material= Stamped SteelHistorical Information:¥ The look is similar to the transition tuning machines used by Gibson during the early 1970s. These tuning machines give you all the same quality Kluson is known for with a metal button to match machine plating.