The spacer rings are mounted between the button and the housing of a closed-type guitar tuner. They increase the distance between the tuner button and the edge of the headstock and provide smooth tuning. Suitable for Duesenberg, Kluson and various other tuners. 25 pieces in black (metal) + 25 pieces in white (plastic).

• Guitar: inner diameter = 4.0mm
• Bass: inner diameter = 5.0mm