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Open-Box Graph Tech Ratio 2+2 Bass Y-Style Button Condition 1 - Mint Black 4 String

Q&A SKU #M01957004001001
90.9 $90.90
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Ratio calibrated machine heads for bass guitars that use a 2 x 2 configuration

The Graph Tech Ratio 2+2 Bass Y-Style Button machine heads deliver predictable, precise tuning, on every string. Each string reacts the same to any tuning adjustment. Graph Tech has balanced the gear ratios to each string, which simplifies the tuning process. With Ratio tuners, a half turn is a semi-tone. The Graph Tech PRB-4220 is a right-handed set of Ratio calibrated machine heads for bass guitars that use a 2 x 2 configuration. To achieve the higher gear ratios, Ratio tuners use a double envelope gear design with a hardened steel gear.


  • Includes:
  • 4 machine heads
  • Mounting screws
  • Bushings

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Ratio 2+2 Bass Y-Style Button Specifications:

  • Gear ratio: 36:1, 30:1, 20:1, 18:1
  • Gear ratio: unique for each string position - one turn-one tone
  • Peg holes diameter required: 35/64" (14mm)
  • String post diameter: 0.547" (13.9mm)
  • String post length to string hole: 1.030" (26.1mm)
  • Weight per single machine head: 1.86oz (53g)
  • Weight per set of four: 7.44oz (212g)
  • String diameter up to 0.98 gauge (or larger if taper-wound)

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Every guitar or bass you purchase from Musician's Friend (electric or acoustic, New or Open Box) includes two years of protection from manufacturer defects.

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