- provide finer tuning control and smooth action, the sealed machine tuning heads will grip your strings for positive and accurate tuning - perfect drop in replacements for LP type guitars without neck modification or adapters, the whole process take your around 20 minutes - 3pcs left guitar tuners+3pcs right locking tuners; 6 bushings; 12 mounting screws - gear ratio: 18:1 for more precise action and provide good amount of resistance, classic look with green keystone tuning knobs, string through shaft - compatible with most Les Paul style electric guitars, or similar series guitars with 8.5mm to 9mm tuning holes, recommend to check your guitar's key holes for exact fitting - decent quality and finish, precise tuning on every string, you can feel the solid and smooth after setup on your guitar, came from an OEM big brand