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4+2 Ratio Lefty Electric Locking Machine Heads Mini Contemporary Button (Black Finish) (PRL-8421-LB0)

4+2 Ratio Lefty Electric Locking Machine Heads Mini Contemporary Button (Black Finish) (PRL-8421-LB0)

PRL-8421-LB0

702725245093

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-8421-LB0 is a left-handed set of Locking RATIO® Calibrated Machine Heads for a Music Man, or other 4 x 2 style headstock.

It has a mini contemporary button.

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.

 

4x2 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: 0.496lbs (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 158 reviews
Total 5 star reviews: 152 Total 4 star reviews: 6 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend these products
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158 reviews
  • NF
    Nardo F.
    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
    16 hours ago
    Amazing keys

    If you have pot metal tuners, toss them out , these are very high quality, and the function off the chart .

  • PP
    Pasi P.
    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
    21 hours ago
    Well worth the price.

    Replaced my puke green machine heads on my ES 135 with these and I am very happy. Fits like a glove...

  • JR
    Joseph R.
    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 4 out of 5 stars
    Yesterday
    Time for a change.

    I liked the ease to install. The quality appears top shelf. Forty years of heavy use destroyed my original machine heads. This was a necessary change to maintain tune. I am pleased with the decision to purchase from graphtech. I'll report back if they fail to function as intended.

  • MT
    Matthew T.
    Verified Buyer
    7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)
    Reviewing
    7 Strings: 3+4 Ratio Electric Locking Machine Heads (PRL-8621, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    2 days ago
    They are very nice tuners

    Hello! I put these tuners on my Jackson JS22-7 string. The post height is subtly lower, but they fit very thick gauge strings and lock. The post height is probably more optimal. I wish I knew that it was possible, and desirable, to buy the black colored adapters and that I would have to use adapter plates. I'm not bagging on the adapter plates - they are an advance, and made installation super easy. I just wish I had the black ones. It stays in tune well. Good stuff!

  • MW
    Mark W.
    Verified Buyer
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)
    Reviewing
    6-In-Line Ratio Electric Locking Machine Heads Staggered Posts (PRL-9721, Select Finish and Button Style)
    I recommend this product
    Rated 5 out of 5 stars
    3 days ago
    Fantastic machine heads

    Fantastic tuners which were a straight swap on my FMT Telecaster. Took all of ten minutes to install and restring. The stock tuners were OK but these are so much better. The ratios of the gearing makes a huge difference. I'm planning to get some for my other guitars. Utterly fabulous!

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