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7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)

7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)

PRL-8621-C7

702725244522

Regular price $187.77 USD
Regular price Sale price $187.77 USD
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Select Finish
Select Button Style

RATIO® patented gear technology
RATIO® - Calibrated Machine Heads incorporate different string gauges into the tuning equation.

From Low B to High E 48:1, 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-8621 is a right-handed set of Locking RATIO® Calibrated Machine Heads for electric guitars that use a 3 x 4 tuner configuration.

Fits many Jackson, Schecter, and Ibanez (selected) style guitars and a lot of acoustic guitars if you want to upgrade to a locking set of machine heads.

 

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.

 

3x4 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: 0.581lbs (266g)
String diameter up to 72 gauge
Includes 7 machine heads, mounting screws and bushings
Includes complimentary 4 sets of aluminum mounting plates

UPGRADE TO PREMIUM PLATED INVISOMATCH View full details
5.0
Rated 5.0 out of 5 stars
Based on 142 reviews
Total 5 star reviews: 137 Total 4 star reviews: 5 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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142 reviews
  • DO
    Danail O.
    Verified Buyer
    3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)
    Reviewing
    3+3 Ratio Acoustic Guitar Machine Heads (PRN-2411, 2421, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    Quality Acoustic Guitar Machine Heads!

    I was looking for a replacement machine heads for one of my acoustic guitars and these happened to be a perfect fit. Build quality is top notch and they turn smoothly. Installation was easy and although I purchased the matching black Invisomatch plates I end up not using them. Overall a fantastic upgrade.

  • ML
    Mark L.
    Verified Buyer
    3+3 Ratio Acoustic Locking Guitar Machine Heads (PRL-8411, PRL-8441, Select Finish and Button Style)
    Reviewing
    3+3 Ratio Acoustic Locking Guitar Machine Heads (PRL-8411, PRL-8441, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    ratio tuners

    nice looking tuners of good quality and ratio makes tuning a breeze

  • SM
    Samuel M.
    Verified Buyer
    6-In-Line Ratio Lefty Electric Locking Machine Heads (PRL-8721-L, PRL-8731-L, Select Finish and Button Style)
    Reviewing
    6-In-Line Ratio Lefty Electric Locking Machine Heads (PRL-8721-L, PRL-8731-L, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    👍

    Perfect drop in fit for my Chapman ML1 stormburst

  • RD
    Rock D.
    Verified Buyer
    6-In-Line Ratio Electric Locking Machine Heads (PRL-8721, 8731, Select Finish and Button Style)
    Reviewing
    6-In-Line Ratio Electric Locking Machine Heads (PRL-8721, 8731, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 month ago
    Best locking machine heads I've used

    Much more precise than average tuners

  • SH
    Steven H.
    Verified Buyer
    5 String 3+2 Bass Ratio Y-Style Button (PRB-5320, Select Finish)
    Reviewing
    5 String 3+2 Bass Ratio Y-Style Button (PRB-5320, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    2 months ago
    Perfect!

    These work exactly as advertised, and are a great replacement/upgrade from stock. Note: some of the tuners may come from the factory tightened a little aggressively - definitely try loosening a bit if you notice one or more aren't turning as easily as they should :)

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