Graph Tech Ratio Machine Heads – Ultimate Control & Precision
Model number PRN-3422-NO is for a right handed set of
Ratio Tuned Open-Back Machine Heads with a Butterbean style button
for acoustic guitar that use three per side tuners.
RATIO® patented gear technology
RATIO® - Calibrated Machine Heads incorporate different string gauges into the tuning equation.
From Low E to High E 39:1, 24:1, 20:1, 14:1, 20:1, 12:1.
We balanced the gear ratios to each string simplifying the tuning process.
With RATIO®, a half-turn is a semi-tone!
Every string reacts the same to any tuning adjustment. Predictable, precise tuning, on every string.
Gear ratio: unique for each string position - one turn-one tone
Peg holes diameter required: 0.346" (8.8mm)
String post diameter: 0.236" (6mm)
String post length to string hole: 0.827” (21mm)
Weight per single machine head: 0.056lbs (25.5g)
Weight per set of six: 0.338lbs (153g)
String diameter up to 72 gauge
Includes 6 machine heads, mounting screws, and bushings