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.

The PRN-2721 and PRN-2731 are a right-handed sets of RATIO® Calibrated Machine Heads for electric guitar that use 6-in-line tuners.

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.

Specification:

• 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: 0.890” (22.6mm)
• Weight per single machine head: 0.066lbs (30g)
• Weight per set of six: 0.393lbs (179g)
• String diameter up to 72 gauge
• Includes 6 machine heads, mounting screws and bushings
• Includes complimentary 4 sets of aluminum mounting plates