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6-In-Line Ratio Lefty Electric Locking Machine Heads Staggered Posts (PRL-9721-L, PRL-9731-L, Select Finish and Button)

6-In-Line Ratio Lefty Electric Locking Machine Heads Staggered Posts (PRL-9721-L, PRL-9731-L, Select Finish and Button)

PRL-9721-LC0

702725248100

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-L and PRL-9731-L are the left-handed sets of Locking RATIO® Calibrated Machine Heads for electric guitars with 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 258 reviews
Total 5 star reviews: 247 Total 4 star reviews: 10 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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258 reviews
  • DS
    Des S.
    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
    1 week ago
    Best Tuners in The World

    Absolutely love ratio tuners. The way all tuners should be. The price may put some people off but really they are competitvely priced against big name tuners like Grover or Gotoh and you're lucky if they are 18:1 ratio.

    I've replaced most of my collection with Ratio tuners and still love my earlier special order for my 12 string acoustic. Stays in tune so well. and now I enjoy picking it up and playing without having to re-tune every time.

    Great customer service and regular updates after placing order.

  • LB
    Larry B.
    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
    Simply the best!

    TSIA

  • CT
    curtis t.
    Verified Buyer
    3+3 Ratio Acoustic Open Back Tuners (PRN-3411, Select Finish)
    Reviewing
    3+3 Ratio Acoustic Open Back Tuners (PRN-3411, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    1 week ago
    Acoustic 3+3 for Guild D55

    I have installed Ratio tuners on other guitars and with the new Guild, it was the first change I decided to make. Much more precise than the OEM Gotoh SE700. BUT, I have not installed these tuners yet as I am waiting for the local luthier to change the nickel finish. I wanted these tuners black, as I have had on the other closed Ratios. Maybe a gentle nudge to offer this finish. The screw holes will have to be filled in as the included screw for the Ratios are a bit less robust than the Gotoh. Still, I am pleased to know that these will soon be installed, along with the TUSQ bridge pins, presentation style, with Paua inlay.

    Nice work from good people!!

  • JR
    Jesus R.
    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 weeks ago
    Excellent product

    Graphtech is the standard for these parts and the customer service and attention is second to none. Thank you so much for all your help and for extremely fast service.

  • RR
    Robert R. M.
    Verified Buyer
    3+3 Ratio Acoustic Open Back Tuners (PRN-3411, Select Finish)
    Reviewing
    3+3 Ratio Acoustic Open Back Tuners (PRN-3411, Select Finish)
    I recommend this product
    Rated 5 out of 5 stars
    2 weeks ago
    Excellent addition to my 000

    Very accurate and hold tune over time.

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