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7 Strings: 7-In-Line Ratio Lefty Electric Locking Machine Heads Staggered Posts (PRL-9721-Lx7, PRL-9731-Lx7, Select Finish and Button)

7 Strings: 7-In-Line Ratio Lefty Electric Locking Machine Heads Staggered Posts (PRL-9721-Lx7, PRL-9731-Lx7, Select Finish and Button)

PRL-9721-LC7

702725248285

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-9721-Lx7 and PRL-9721-Lx7 are the left-handed sets of Locking RATIO® Calibrated Machine Heads for electric guitars with 7-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 seven: 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 233 reviews
Total 5 star reviews: 223 Total 4 star reviews: 10 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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233 reviews
  • D(
    Donat (Woody) L.
    Verified Buyer
    3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)
    Reviewing
    3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)
    I recommend this product
    Rated 5 out of 5 stars
    Yesterday
    Best Tuners

    This is my 3rd guitar that I have replaced tuners and I am very happy with these. Makes tuning easier and faster and fine tuning a breeze.

  • GY
    Georgy Y.
    Verified Buyer
    6-In-Line Retro Fender Style Ratio Machine Heads (PRN-4624-N0, Nickel Finish)
    Reviewing
    6-In-Line Retro Fender Style Ratio Machine Heads (PRN-4624-N0, Nickel Finish)
    I recommend this product
    Rated 5 out of 5 stars
    6 days ago
    Those things handle Bass VI strings with ease

    I have Fender Vintera II Bass VI, it came with retro tuning machines and I broke 1 by stripping brass gear.

    Installation is very easy, and no hole reaming was required.

    Included screws were too small so I reused original ones.

    This set handles bass string properly.

    Instead of suggested order I just installed tuning machines in ratio order, as all strings are wound and there are no treble strings.

    The string set is .024 .034 .044 .065 .080 .100, 30” scale

    Finally I don’t have to do a 1/360th turn to tune E.

    While not specifically designed for bass strings I still get major benefits of more accurate tuning across all strings.

    It was a complete shock honestly to discover that guitars still use same gear ratio across different gauges.

    Only downside is that screws holding tuning buttons came loose during first 30 minutes of playing, I added a drop of blue threadlocker and now it’s all good. Obviously it’s not enough to take a star off.

  • JT
    James T.
    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
    1 week ago
    Outstanding!

    I flat out love them! Well worth the price! They should come as standard equipment on every guitar! 🎸

  • MK
    Michael K.
    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
    2 weeks ago
    Great option for locking and precision tuning

    This is my second set of ratio tuners I’ve purchased for an Ibanez RG series guitar and they fit great and the precision of getting your guitar tuning dialed in is amazing.

  • GC
    Garry C.
    Verified Buyer
    3+3 Ratio Acoustic Guitar Machine Heads Gold Finish. "45 Degree mounting screw"  (GT-118-D0)
    Reviewing
    3+3 Ratio Acoustic Guitar Machine Heads Gold Finish. "45 Degree mounting screw" (GT-118-D0)
    I recommend this product
    Rated 5 out of 5 stars
    2 weeks ago
    Quality Machine Heads

    Very well made, they don't feel flimsy or weak & the tuning is precise, these being the lowest cost model that I tried first & installed a few days ago, very happy with the look & feel but the precision is the most important thing to me as correct precise tuning is paramount!

    I would definitely recommend these to friends & family

    And will purchase the locking tuners ASAP Especially since the quality & precision are better than

    Any others I tried in this price range,

    The packaging & instructions plus the money back Guarantee/Quality is simply a win win situation!

    As a student appreciate Luthier who's just about to complete my first year at college, I need Quality parts that are the best value for the Money as my real passion is Restoring & Repair/upgrading old Guitar's that just need TLC & Great parts to bring them back to their best or better, thanks to everyone at Graphtech for the hard work building Quality parts that all Instruments deserve!

    Best Regards

    Garry @ Triple G's,

    {God's Grace Guitar's}

    "One Love to the World 🌍 from Bonnie Scotland"🏴󠁧󠁢󠁳󠁣󠁴󠁿

    ☝️❤️🌎🏴󠁧󠁢󠁳󠁣󠁴󠁿🍀🌈🕊️♾️🙏🌞🌕🌟💪

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