Instrument Compatibility: Best suited for vintage or standard style electric basses, such as a Fender Jazz Bass or Precision Bass.Design Type: Open-gear architecture, which provides direct tuning stability and easy access for maintenance and lubrication.Button Style: Traditional chrome-plated cloverleaf keys.Configuration: This is a pack of 4 matching tuners. Before buying or replacing, check your bass headstock layout to confirm if it requires a 4-In-Line setup (all on one side) or a 2-Left/2-Right split layout.