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
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RATIOĀ® patented gear technology
RATIOĀ® - 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 RATIOĀ®, a half-turn is a semi-tone!
Every string reacts the same to any tuning adjustment. Predictable, precise tuning, on every string.
The PRL-9721-LĀ andĀ PRL-9731-LĀ are the left-handedĀ sets of Locking RATIOĀ® 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.
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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: 0.827ā (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
Invisomatch Adapter Plates
Ā Ā InvisoMatchĀ® Adapter Plates offerĀ the easiest solution for installing RATIOĀ® Tuned Machine Heads on your guitar
No drilling, perfect alignment, fast installation!
The alignment of the machine heads is perfect, no holes to drill or fill, ideal for vintage instruments. Premium finishes are available for order, including chrome, nickel, black, and gold. Additionally, each set of RATIOĀ® Tuners comes with four complimentary brushed aluminum InvisoMatchĀ® Adapter Plates.*
*Each set of Graph Tech RATIOĀ® Machine Heads includes four sets of brushed aluminum InvisoMatchĀ® Adapter Plates. These plates are not included with bass or open back tuners. āFor a customized appearance,Ā Ā are available in finishes such as chrome, black, nickel, and gold.Ā
Find your InvisoMatchĀ® Adapter Plates fit (download the guide!)
Please note that our InvisoMatchĀ® Adapter Plates list is regularly updated. Before placing your order, ensure the selected plate matches your guitar's specific model and variation.
* Some guitars may have different configurations, so double-checking compatibility is essential.Ā
Simply select the installation plate design that matches the screw/pin hole location of your factory installed machine heads. Youāll be up and running within minutes, perfectly installed and aligned. Stay classy you axe master.
For stunning accuracy and response... upgrade to RATIOĀ® Machine HeadsĀ with it's patentedĀ Multi-Geared Tuning Technology. The new standard in tuning.
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Graph Tech has created some of the world's most recognized products and brands in the music industry
The list of industry firsts include the world's first self-lubricating nut in 1983, String Saver Saddles the first saddle to drastically reduce string breakage, TUSQ man-made ivory, and Ratio machine heads.
Graph Tech has over 50 patents and trademarks around the world.
- MSMichael S.Verified BuyerReviewing3+3 Ratio Electric Guitar Machine Heads (PRN-2311, 2341, please select finish and button style)I recommend this productRated 5 out of 5 stars2 weeks agoGreat!!
This might be obvious, but when installing, put the tuner into the plate before putting the screws into the headstock plates. If you put the screws into the plates first the tangs of the tuner might not fit well into the plate. The work wonderfully when installed.
- BDBradley D.Verified BuyerReviewing6-In-Line Ratio Lefty Electric Locking Machine Heads (PRL-8721-L, PRL-8731-L, Select Finish and Button Style)I recommend this productRated 5 out of 5 stars3 weeks agoReplace machine heads
Very good product
- JAJames A.Verified BuyerReviewing3+3 RATIO Lefty Electric Locking Machine Head Vintage Button (PRL-8341-L, Select Finish)I recommend this productRated 5 out of 5 stars3 weeks agoThe Best There Is
These tuning machines are outstanding.
- PFPete F.Verified BuyerReviewing3+3 Ratio Acoustic Guitar Machine Heads Gold Finish. "45 Degree mounting screw" (GT-118-D0)I recommend this productRated 5 out of 5 stars1 month agoGame changer in tuning accuracy!
Fit perfectly.
look great.
Fine tuning is now a breeze.
Hold tuning well.
- PTPhilip T.Verified BuyerReviewing7 STRINGS: 7-in-line Ratio Lefty Electric Locking Machine Heads (PRL-8721-Lx7, Select Finish)I recommend this productRated 5 out of 5 stars1 month agoAmazing as always!
Every guitar I put these on, it just makes it perfect. Much easier to change strings. The feel of the tuning needle slowing down in time and being able to tune with pin-point precision is just excellent.