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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
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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-8721 and PRL-8731 are right-handed sets of Locking RATIO® Calibrated Machine Heads for electric guitars 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

UPGRADE TO PREMIUM PLATED INVISOMATCH View full details
5.0
Rated 5.0 out of 5 stars
Based on 212 reviews
Total 5 star reviews: 203 Total 4 star reviews: 9 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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212 reviews
  • GG
    George G.
    Verified Buyer
    3+3 Ratio Electric Locking Machine Heads (PRL-8311, 8322, 8331, 8341, 8351)
    Reviewing
    3+3 Ratio Electric Locking Machine Heads (PRL-8311, 8322, 8331, 8341, 8351)
    I recommend this product
    Rated 5 out of 5 stars
    5 days ago
    Non Better

    Great product! these are my third set that I purchased. Never disappointed with you guys!

  • DF
    Daniel F.
    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 week ago
    Awesome!

    Maybe the best I've ever tried!

  • AP Profile picture for Alex P.
    Alex P.
    Verified Buyer
    7 STRINGS: 7-in-line Electric Locking Machine Heads (PRL-8721-C7, Select Finish)
    Reviewing
    7 STRINGS: 7-in-line Electric Locking Machine Heads (PRL-8721-C7, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    Perfect!

    These fit my Ibanez RG7321 perfectly. Took less than 10 minutes to install. Didn’t even need to use the adapter plates or use any screws. Strings are Daddario 10-60 but you could easily fit heavier gauge if needed.

  • JB
    Jared B.
    Verified Buyer
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, 9731, Select Finish and Button Style)
    Reviewing
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, 9731, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    Great Tuning Machines

    Very quick string changes, quick tuning and nice smooth operation!

  • KB
    Kenneth B.
    Verified Buyer
    3+3 RATIO Lefty Electric Locking Machine Head Vintage Button (PRL-8341-L, Select Finish)
    Reviewing
    3+3 RATIO Lefty Electric Locking Machine Head Vintage Button (PRL-8341-L, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    3 weeks ago
    Well made product

    As a lefty, I appreciate a quality product made specifically for a left handed guitar.

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