Understring Radius Gauges

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Understring Radius Gauges Standard width, set of 9

Standard width, set of 9

Item # 0353
In stock, ready to ship!


Understring Radius Gauges Extra-wide, set of 9

Extra-wide, set of 9

Item # 0359
In stock, ready to ship!


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Understring Radius Gauges

About This Item

Fast, accurate bridge saddle adjustment.
Each of these unique gauges has an accurately radiused arc on both the top and bottom surfaces, and is shaped to fit easily under the strings.

Use the bottom curvature to determine your fretboard radius, and the matching top curvature becomes a reference for setting string saddle heights for best playability.

Low profile fits tight spots. The slim shape of our understring gauges allow you to read the fretboard radius even with the strings on! This is also handy for matching pickup polepiece heights to the arc of the strings. And setting bridge saddles is easier than ever.

The set of 9 gauges includes:
7-1/4", 9-1/2", 10", 12", 14", 15", 16", 17" and 20" radii.

Standard width 6-string guitars and most 4-string basses—spans a string spread up to 2-5/8" (66.68mm).

Extra-wide covers string spreads up to 3-3/4" (95.25mm)—enough for 4-string, 5-string, and many 6-string basses. They'll also handle 7-string and 8-string guitars.

Stainless steel.


Trade Secrets!

Trade Secrets!

Fixing fret buzz: raising the saddles

A P-Bass with fret buzz: Dan Erlewine fixes his brother’s bass, and answers the question, “To get rid of this fret buzz, should I adjust the saddles or the truss rod?”

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  • 4.95 average rating from 157 reviews
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the piece needed

(Customer's Reviews)

the bridge and the keys so I came gwnial to work much more precisely and in detail.
the bridge an incredible piece stability and accuracy to the maximum
Thank you !!!


Great tool for 8 string guitars.

(Customer's Reviews)

Works very well with an 8 string Ibanez RG. I would consider this tool essential, especially with individually adjustable saddles. Also great for measuring the actual radius of the fingerboard, which in my case was 16" instead of the 17" stated on the specs.


Great tool

(Customer's Reviews)

These are really handy for setting up a guitar! I would be nice if they came with a ring, but you can pick one up pretty cheaply.

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StewMac PDF Catalog, page 17 See Understring Radius Gauges
on page 17 of our StewMac Catalog PDF

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