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6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)

6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)

PRL-9721-B0

702725245086

Regular price $160.94 USD
Regular price Sale price $160.94 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 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-9721 is a right-handed set of Locking RATIO® Calibrated Machine Heads for electric guitars 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.

 

6-in-line tuners set Staggered 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: 0.827” (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

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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