Tuner

    Grover 406 Rotomatic 18:1

    Grover's classic sealed-gear Rotomatic tuner, 18:1 ratio, a long-standing standard replacement for vintage-style tuners on 10mm-hole guitars.

    25 guitars checked: 16 likely drop-in, 9 needs verification.

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    Where to buy

    Amazon

    Price not publishedIn stock

    Being re-verified

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    Part specs

    Tuner hole size

    10mm

    Confirmed

    Gear ratio

    18:1

    Confirmed

    Mounting pattern

    Single rear mounting screw with a threaded hex peghead bushing.

    Confirmed

    Installation notes

    Grover Rotomatics are the standard 10mm-hole reference point for tuners generally, a common drop-in on any guitar already using modern 10mm tuner bushings.

    Guitars we've checked

    25 guitars checked: 16 likely drop-in, 9 needs verification.

    Epiphone ES-335

    Epiphone

    ES-335 2021

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    The Epiphone ES-335 has a Gibson-style 3-per-side headstock drilled at 10mm. Grover's Rotomatic housing is built for a 10mm bore, so the posts seat in the existing holes.

    Epiphone Jimi Hendrix Flying V Left-Handed

    Epiphone

    Jimi Hendrix Flying V Left-Handed

    Likely drop-in

    Should swap straight into the existing tuner holes, no reaming needed. This tuner set is not handed, so the same part works on this left-handed guitar.

    Why we say this

    Standard 3+3 Gibson-style footprint, 10mm holes. Gibson and PRS-style 3-per-side tuner sets are not handedness-specific, so this fits the left-handed guitar without needing a separate SKU.

    Epiphone Les Paul Custom

    Epiphone

    Les Paul Custom 2020

    Likely drop-in

    Matches this guitar's confirmed 10mm tuner holes directly, an easy swap within the same tuner family it already ships with.

    Why we say this

    This guitar already ships with Grover Rotomatic tuners at a confirmed 10mm hole size, so a same-family Grover swap is about as safe a fit claim as there is.

    Epiphone Les Paul Standard 60s

    Epiphone

    Les Paul Standard 60s 2020

    Likely drop-in

    Matches this guitar's confirmed 10mm tuner holes. Some units of this guitar shipped with a different tuner brand than usual, so it is worth checking what you actually have installed before buying, even though the hole size itself is confirmed.

    Why we say this

    This guitar's tuner hole size is confirmed at 10mm, matching this tuner directly. Some production units of this model have shipped with Wilkinson tuners instead of the usual Grover Rotomatics, so confirm what you actually have installed before assuming this is a same-brand swap, though the hole size itself is confirmed regardless of which brand shipped.

    ESP LTD Viper 400

    ESP

    LTD Viper 400 2021

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. It already ships with Grover tuners, so this is a direct like-for-like swap.

    Why we say this

    The Viper 400 has a 3-per-side headstock drilled at 10mm and leaves the factory with Grover tuners already fitted, so this is a like-for-like replacement of the stock part.

    Gibson ES-339

    Gibson

    ES-339 2021

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    The ES-339 uses the same headstock hardware as the ES-335, drilled at 10mm. Grover's Rotomatic housing is built for a 10mm bore, so the posts seat in the existing holes.

    Gibson Flying V

    Gibson

    Flying V 2019

    Likely drop-in

    Should swap straight into the existing tuner holes, no reaming needed.

    Why we say this

    Gibson's own spec sheet for this model confirms Grover tuners on the standard 3+3 footprint.

    Gibson Les Paul Classic

    Gibson

    Les Paul Classic 2023

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    Standard Gibson 3-per-side headstock drilled at 10mm. Grover's Rotomatic housing is built for a 10mm bore, so the posts seat in the existing holes.

    Gibson Les Paul Modern

    Gibson

    Les Paul Modern 2020

    Likely drop-in

    Should swap straight into the existing tuner holes, no reaming needed.

    Why we say this

    Ships with locking Grover Rotomatic tuners on the standard Gibson 3+3 footprint, no caveats noted.

    Gibson Les Paul Standard '60s Left-Handed

    Gibson

    Les Paul Standard '60s Left-Handed

    Likely drop-in

    Should swap straight into the existing tuner holes, no reaming needed. This tuner set is not handed, so the same part works on this left-handed guitar.

    Why we say this

    Same hardware footprint as the right-handed Les Paul Standard 60s. Gibson/PRS 3-per-side tuner sets are not handedness-specific, so no separate left-handed SKU is needed.

    Gibson Les Paul Standard 60s

    Gibson

    Les Paul Standard 60s 2023

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    Standard Gibson 3-per-side headstock drilled at 10mm. Grover's Rotomatic housing is built for a 10mm bore, so the posts seat in the existing holes.

    Gibson SG Standard

    Gibson

    SG Standard 2023

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    Standard Gibson 3-per-side headstock drilled at 10mm, and Grover's Rotomatic housing is built for a 10mm bore. The unresolved question on this model is its bridge post spacing, which has no bearing on tuner fit.

    Gibson SG Standard 61

    Gibson

    SG Standard 61 2023

    Likely drop-in

    Grover's Rotomatics are built for 10mm holes, which is what this guitar has. Straight swap, no reaming.

    Why we say this

    Standard Gibson 3-per-side headstock drilled at 10mm, and Grover's Rotomatic housing is built for a 10mm bore. The unresolved question on this model is which tailpiece is fitted, which has no bearing on tuner fit.

    Gibson SG Standard Left-Handed

    Gibson

    SG Standard Left-Handed

    Likely drop-in

    Should swap straight into the existing tuner holes, no reaming needed. This tuner set is not handed, so the same part works on this left-handed guitar.

    Why we say this

    Standard Gibson 3+3 footprint, 10mm holes. Gibson/PRS 3-per-side tuner sets are not handedness-specific.

    ESP

    E-II Eclipse 2022

    Needs verification

    The tuner hole size matches, but this guitar's screw mounting pattern is angled differently from a standard mount. The screw holes may not line up even if the post itself fits.

    Why we say this

    Hipshot's own fitment guidance for the ESP LTD Eclipse states tuner mounting screw holes are angled 45 degrees from the tuner body, a nonstandard pattern that may not align with a standard two-screw mount even though the peghole diameter matches.

    Help confirm this fit

    ESP

    E-II Eclipse EverTune 2022

    Needs verification

    The tuner hole size matches, but this guitar's screw mounting pattern is angled differently from a standard mount. The screw holes may not line up even if the post itself fits.

    Why we say this

    Shares the same Eclipse-body headstock as the standard E-II Eclipse, where Hipshot's own fitment guidance confirms a nonstandard 45-degree angled screw mount.

    Help confirm this fit

    ESP

    E-II Eclipse Full Thickness 2022

    Needs verification

    The tuner hole size matches, but this guitar's screw mounting pattern is angled differently from a standard mount. The screw holes may not line up even if the post itself fits.

    Why we say this

    Shares the same Eclipse-body headstock as the standard E-II Eclipse, where Hipshot's own fitment guidance confirms a nonstandard 45-degree angled screw mount.

    Help confirm this fit

    ESP

    E-II Eclipse Full Thickness EverTune 2022

    Needs verification

    The tuner hole size matches, but this guitar's screw mounting pattern is angled differently from a standard mount. The screw holes may not line up even if the post itself fits.

    Why we say this

    Shares the same Eclipse-body headstock as the standard E-II Eclipse, where Hipshot's own fitment guidance confirms a nonstandard 45-degree angled screw mount.

    Help confirm this fit

    ESP LTD EC-1000

    ESP

    LTD EC-1000 2023

    Needs verification

    The tuner hole size matches, but this guitar's screw mounting pattern is angled differently from a standard mount. The screw holes may not line up even if the post itself fits.

    Why we say this

    The LTD EC series shares the same Eclipse-body headstock design as the E-II Eclipse, where Hipshot's own fitment guidance confirms a nonstandard 45-degree angled screw mount.

    Help confirm this fit

    Gibson ES-335

    Gibson

    ES-335 2021

    Needs verification

    Hole size should be close, but tuners on this model have varied by year. Confirm your actual tuner post diameter before ordering.

    Why we say this

    Tuners on the Gibson ES-335 have varied by production year between Vintage Deluxe, Grover, and Kluson units on roughly 10mm posts, rather than one settled spec. Grover's Rotomatic housing needs a 10mm bore, so the general size is close, but bushing fit can differ depending on which year's tuners are actually fitted.

    Help confirm this fit

    Gretsch G6120T

    Gretsch

    G6120T 2022

    Needs verification

    Hole size should be close, but Gretsch tuner mounting patterns vary by model and this one has not been confirmed. Worth checking screw hole spacing before ordering.

    Why we say this

    Gretsch tuner mounting conventions vary meaningfully by model, this has not been confirmed for the G6120T specifically, and forum reports are mixed across the Gretsch range.

    Help confirm this fit

    Hagstrom

    Ultra Swede

    Needs verification

    Hagstrom does not publish the Ultra Swede's tuner hole size, so we cannot confirm this drops straight in. Measure your existing tuner posts before buying.

    Why we say this

    The Ultra Swede ships with Hagstrom's own non-locking 18:1 die cast tuners, and Hagstrom does not publish the tuner post hole size for this model, so fitment against Grover's standard 10mm hole cannot be confirmed either way.

    Help confirm this fit

    Hagstrom Viking

    Hagstrom

    Viking 2014

    Needs verification

    A popular tuner upgrade, but Hagstrom does not publish the Viking's tuner hole size, so we cannot confirm this drops straight in. Measure your existing tuner posts before buying.

    Why we say this

    Grover's Rotomatic is the standard 10mm hole reference point across most modern guitars, but Hagstrom's current die cast tuner hole size on the Viking is not published anywhere, and older Hagstrom models are documented using odd, non-standard hole sizes, so 10mm compatibility cannot be assumed the way it can on a modern Gibson or Epiphone.

    Help confirm this fit

    This page has 9 open questions

    If you have fitted any of these to this 406 Rotomatic 18:1, tell us what you found and we'll update the data.