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Graph Tech Guitar
6-in-line Left-Handed Ratio Electric Locking Machine Heads Staggered Posts, Black
Item ID: PRL-9721-LB0

List Price: $209.22


The PRL-9721 is a set of Locking RATIO® Calibrated Machine Heads for electric guitar that use 6-in-line tuners with staggered posts (eliminates the need for a string tree). It has a two pin casing that can be used as is, or with our Patented InvisoMatch Mounting Plates [opens in new tab]. 4 different sets of InvisoMatch mounting plates in brushed aluminum are included to make installation on most guitars fast and accurate by using your existing screw mounting holes.
  • 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, 35:1, 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: 13/32" (10mm)
  • String post diameter: 0.236" (6mm)
  • String post length to string hole: 0.827” (21mm) - 0.787" (20mm) - 0.748" (19mm)
  • Weight per single machine head: 0.083lbs (38g)
  • Weight per set of six: 0.496lbs (225g)
  • String diameter up to 72 gauge
  • Includes 6 machine heads, mounting screws and bushings
  • Includes complimentary 4 sets of aluminum mounting plates