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6-In-Line Ratio Electric Locking Machine Heads (PRL-8721, 8731, Select Finish and Button Style)

6-In-Line Ratio Electric Locking Machine Heads (PRL-8721, 8731, Select Finish and Button Style)

PRL-8721-C0

702725245833

Regular price $160.94 USD
Regular price Sale price $160.94 USD
Sale Sold out
Select Finish
Select Button Style

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.

RATIO Machine Heads explanation video

 

The PRL-8721 and PRL-8731 are a right-handed sets of Locking 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.

 

6-in-line tuners set  Ratio Tuned Machine Heads: The New Standard In Tuning Technology

 

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: 0.910” (23mm)
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

Staggered Ratio Measurements.pdfRatio Installation Guide.pdfRatio Installation Guide Video
Moss Hart

Reviewed in the United States on February 15, 2020

Amazon Verified Purchase

 

UPGRADE TO PREMIUM PLATED INVISOMATCH View full details
5.0
Rated 5.0 stars
Based on 8 reviews
Total 5 star reviews: 8 Total 4 star reviews: 0 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend this product
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8 reviews
  • IM
    Ian M.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    1 month ago
    Black Ratios

    Loved them. The engineering is superb and the finish was perfect. They really finished of my guitar. I liked the added plectrums, I'm now looking to decide my preference and lay in a supply

  • DP
    Darwin P.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    2 months ago
    The Right Stuff

    I bought the black color in the 6-in-line ratio locking machine heads and chose the contemporary style. I installed them on a blonde Squier Affinity Telecaster. I still need to add black backing plates in the future to cover the holes left when I removed the machine heads that came on the guitar. This did not happen when I installed them on a Squier Affinity Stratocaster. Now, I'll tell you what I think of the quality of this product. Everything that the advertising said would happen when I bought them is true. They are easy to install, changing strings with the locking mechanism is a snap, adjusting to barely having to turn the smooth metal head when it is time to retune each string takes very little time and the way that they look on the guitar is super. I would highly recommend these ratio electric locking machine heads to anyone wishing to upgrade their guitar.

  • RM
    Russell M.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    5 months ago
    Custom guitar build

    High quality parts, very satisfied.

  • ES
    Edward S.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    5 months ago
    As advertised

    These tuners do what they say they do. There isn't much else to say.

  • GG
    George G.
    Verified Buyer
    I recommend this product
    Rated 5 stars
    6 months ago
    They Fit G & L Bluse Boy

    Before making my purchase, I tried fitting my Fender Telecaster MH to my G & L Bluse Boy, and the pin holes we off by 1/32. I was certain that I would be using one of the universal mounting plates. When my Graphtech MH arrived, they were a perfect match to my Bluse Boy, no plate was needed. Many thanks guys!

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