What Is an ABR-1 Bridge? How to Spot One, Post Specs, and Which Replacement Fits
An ABR-1 is Gibson’s original Tune-o-matic bridge: a narrow bridge with six adjustable saddles on two thin 6-32 posts with separate thumbwheels. On vintage, Custom Shop and Historic guitars, the posts screw straight into the wood. On a few select Gibson USA models from 2017, and all Original Collection models since 2019, the same ABR-1 sits on one-piece posts in body bushings. The Faber ABRH drops onto both.
Below: how to tell if you have one, the post specs that matter, and which Faber bridge to order.
Jump to: What it is · How to tell · Specs · Which bridge fits · FAQ
What an ABR-1 bridge is
The ABR-1 has a bridge body, six saddles with intonation screws and, on stock Gibson bridges, a saddle retaining wire. It sits on two 6-32 posts, and the thumbwheels on those posts set the bridge height. “Tune-o-matic” is the general name for this style of bridge; the ABR-1 is Gibson’s original model. For how it differs from the Nashville, see Nashville vs ABR-1: how to tell.
How to tell if your guitar has an ABR-1
Look at the posts, not just the bridge.
- Thin posts threaded the full length, screwed straight into the wood, with separate thumbwheels and no metal bushing: a classic ABR-1. Common on vintage, Custom Shop and Historic guitars.
- An ABR-1-sized bridge on one-piece posts in metal body bushings, with the upper post smooth above the thumbwheel: the Gibson USA bushing-mount ABR-1 (2017 and later). It’s still an ABR-1 on top.
- A wider bridge on one-piece posts in bushings, with the saddle screw heads usually facing the tailpiece: that’s a Nashville, not an ABR-1.
Full 30-second checklist and side-by-side specs: Nashville vs ABR-1 Bridge: Differences and How to Tell. Photo help: Which Gibson Bridge Do I Have?, or send me a photo through Contact Us.
ABR-1 specs at a glance
| Post thread | 6-32 (inch) |
| Faber ABR-1 post diameter | .132″ (3.35mm) |
| Faber ABRH post spacing | 2.898″ (73.6mm) |
| Faber ABRH post hole | .144″ (3.65mm) |
| Thumbwheels | Separate on the classic ABR-1; built into the factory post on the 2017+ Gibson USA bushing system |
| Upper post, 2017+ factory bushing posts | About 3.65mm, smooth (unthreaded) |
| Saddle screw heads (typical stock) | Face the pickups |
How to measure your own posts: Guitar Bridge Posts Explained. Need a single thumbwheel? See Tune-o-matic Thumbwheels.
Which replacement fits your ABR-1
| Your ABR-1 | Non-locking | Locking | Posts |
|---|---|---|---|
| Classic ABR-1 (posts in the wood) | Faber ABRH on your existing posts and thumbwheels | Tone-Lock Bridge for Gibson with ABR-1 on your factory 6-32 posts, with its included lock nuts | Keep your existing 6-32 posts. Worn or damaged? ABR-1 Style posts with thumbwheels (#3082) |
| Gibson USA ABR-1 on bushings (2017+) | Faber ABRH on your factory posts as is | Tone-Lock Bridge for USA/ABR-1, “EZ” or “PLUS” (includes the posts) | “EZ” #3052 (steel, keeps your bushings) or “PLUS” #3117 (German bell brass, replaces the bushings) |
Classic ABR-1 (vintage, Custom Shop, Historic)
The Faber ABRH drops onto your existing 6-32 posts and thumbwheels. It has no retaining wire, so it’s solid and rattle-free, and the saddles are removable. For a locking bridge, the Tone-Lock Bridge for Gibson with ABR-1 drops onto the same factory posts with its included pair of 6-32 lock nuts: #3031-0 Gloss Nickel, #3031-1 Aged Nickel, #3031-4 Gloss Gold or #3031-5 Aged Gold.
Optional: Gibson drills its ABR-1 post holes about 1″ deep but seats shorter posts about halfway. To seat the posts deeper, you can fit Faber Extra Long ABR-1 posts (#3084) and keep your original thumbwheels. Measure the depth of your post holes first, since some newer Historic and Custom Shop models aren’t drilled 1″ deep. You don’t need them to fit either bridge.
2017+ Gibson USA with the ABR-1 on bushings
The ABRH sits on your factory posts as is. A Tone-Lock bridge needs threaded upper posts for its lock nuts, so on this system it comes as the Tone-Lock Bridge for USA/ABR-1 with Faber “EZ” (#3052) or “PLUS” (#3117) posts, or you can add USA/ABR-1 conversion posts on their own. Full upgrade path: ABR-1 Bridge on a Gibson USA.
Have a Nashville instead?
For a Nashville Gibson, Faber’s ABR-1 style options use conversion posts. See How to Convert a Gibson Nashville Bridge to ABR-1 Style.
Locking or non-locking?
The ABRH is the non-locking, no-wire choice. A Tone-Lock bridge adds lock nuts on threaded posts that lock the bridge to the thumbwheel: one continuous, solid connection from the top of the bridge through the thumbwheel. The bridge stays put when you change strings, and the height stays set. The large upper post holes in a Tone-Lock bridge are there for the lock nuts. Set-screw locking bridges work differently: they clamp the bridge to the posts, and you can still spin the thumbwheel down while locked.
See all Faber Tone-Lock Bridges, and watch “How to install Faber® Tone-Lock™ Bridge” on the How-To-Videos page.
Saddles and finishes
Every Faber bridge comes with Pre-Notched saddles, installed and ready to play. Brass saddles are standard: nickel plated on the nickel finishes, gold plated brass on Gloss Gold and aged gold plated brass on Aged Gold. The ABRH comes in four finishes:
- #3023-0 ABRH Bridge, Gloss Nickel
- #3023-1 ABRH Bridge, Aged Nickel
- #3023-4 ABRH Bridge, Gloss Gold
- #3023-5 ABRH Bridge, Aged Gold
Changing saddles only? See Replacement Tune-o-matic Saddles.
Or get it all at once
A Tone-Lock Master Kit for Gibson with ABR-1 puts a Tone-Lock bridge, a TP-59 tailpiece and Tone-Lock tailpiece studs in one box. Choosing a tailpiece on its own? See the stop tailpiece guide.
ABR-1 bridge FAQ
What is an ABR-1 bridge?
The ABR-1 is Gibson’s original Tune-o-matic bridge. It’s a narrow bridge with six adjustable saddles that sits on two thin 6-32 posts with separate thumbwheels for height.
How do I know if my guitar has an ABR-1?
Look at the posts. Thin posts screwed straight into the wood with separate thumbwheels mean a classic ABR-1. An ABR-1-sized bridge on one-piece posts in metal bushings is the 2017+ Gibson USA version. A wider bridge on bushings is a Nashville.
What size are ABR-1 bridge posts?
ABR-1 posts use a 6-32 inch thread. Faber’s ABR-1 posts are .132″ (3.35mm) in diameter, and the Faber ABRH has 2.898″ (73.6mm) post spacing with .144″ (3.65mm) post holes.
What replacement bridge fits a Gibson ABR-1?
The Faber ABRH drops onto your existing 6-32 posts and thumbwheels with no modification. For a locking bridge, the Tone-Lock Bridge for Gibson with ABR-1 also drops onto your factory 6-32 posts with its included lock nuts.
Will a Faber ABRH fit my 2017 or newer Gibson USA with bushings?
Yes. The ABRH sits on your factory posts as is. A locking Tone-Lock bridge needs Faber “EZ” (#3052) or “PLUS” (#3117) USA/ABR-1 posts, or a Tone-Lock bridge or Master Kit that already includes them.
Is an ABR-1 the same as a Tune-o-matic?
The ABR-1 is one Tune-o-matic bridge, Gibson’s original model. “Tune-o-matic” is the general name for this style of bridge; the Nashville is another.
Do I need longer posts for my ABR-1?
Not to fit a Faber bridge. The ABRH and the Tone-Lock Bridge for ABR-1 both fit your factory 6-32 posts. Some owners fit Faber Extra Long ABR-1 posts (#3084) to seat the posts deeper; measure your post hole depth first, since some newer Historic and Custom Shop guitars aren’t drilled 1″ deep.
Related reading
- Nashville vs ABR-1 Bridge: Differences and How to Tell
- ABR-1 Bridge on a Gibson USA
- Guitar Bridge Posts Explained
- Gibson Les Paul Bridge Replacement: Which Bridge Fits Your Les Paul?
- Products for Gibson Guitars with ABR-1 Bridges
- Products for Gibson Guitars with USA/ABR-1 Bridges
- USA/ABR-1 info and videos