4mm Allen Nut Hot Rod Truss Rod

  • 96 Reviews
  • Write a review

A smaller 4mm (5/32") Allen nut for most instruments. Smooth two-way action corrects upbow and backbow, giving complete control over the neck.

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12-1/4" overall length

Item # 2550
In stock, ready to ship!


6 or more $13.74
12 or more $12.95

14-1/4" overall length

Item # 2551
In stock, ready to ship!


6 or more $13.91
12 or more $13.11

18" overall length

Item # 2552
In stock, ready to ship!


6 or more $14.78
12 or more $13.93

24" overall length

Item # 2553
In stock, ready to ship!


6 or more $18.26
12 or more $17.21
Quantity Discount Prices apply when you buy multiples of the same item number.
Total: $0.00
Quantity: 20


A smaller 4mm (5/32") Allen nut for most instruments. Smooth two-way action corrects upbow and backbow, giving complete control over the neck.

Easy to install. The Hot Rod® fits in a straight channel. For proper operation, this truss rod must be installed so that the active rod (the rod with the adjustment nut) is below the passive rod. A wooden filler stick is not required.

Smooth 2-way action with superior strength for stubborn necks.
Our Hot Rod neck adjustment system features twin rods in threaded brass collars. The stainless steel active rod turns for smooth neck alignment, with 2-way action to correct upbow and backbow.

The Hot Rod requires an access cavity for the adjustment nut, and a straight 7/32"-wide x 7/16"-deep slot (measured from the bottom of the fretboard) for installation.

Pick the Hot Rod Truss Rod size you'll need:
(overall length includes the nut)

Resonator guitar
Acoustic guitar with 12th fret at the body
Acoustic guitar with 14th fret at the body
Electric guitar

We've designed the Router Bit for Hot Rod Truss Rods especially for routing your neck to fit our truss rods.

Product Instructions

Hot Rod Adjustable Truss Rods

Installation and adjustment instructions for Hot Rod Adjustable Truss Rod.

    • Item #
    • Weight
    • 2550
    • 0.197
    • 2551
    • 0.232
    • 2552
    • 0.296
    • 2553
    • 0.385

Ratings & Reviews

4mm Allen Nut Hot Rod Truss Rod

  • Based on 96 Reviews
Displaying 6 of 10 1 2 3 4 5 6 7 8 9 10
Write a review

Good Truss Rod

By Ben Fleenor from Waynesville, NC
(Customer's Reviews) Tuesday, January 17, 2012

I've used several of these and they get the job done. My only complaints would be the odd dimensions (7/32 width in particular) and that it has a rod for the top piece instead of a flat bar. The price is great though.

hot rodding my new guitar

By lefty's rule from duluth mn
(Customer's Reviews) Tuesday, January 17, 2012

i bought 2 of these rods and they work great.

Fantastic Truss Rods

By Equilibrium Guitars from Somerville, MA
(Customer's Reviews) Saturday, January 14, 2012

I use these in every custom guitar and bass I make. They are effortless to install using the correct router bit, and provide tremendous control over the neck.

By using two carbon fiber reinforcements on either side of the truss rod, even a 28.5" scale 8-string can be adjusted easily.

installing truss rods

By zex guitars from Serbia
(Customer's Reviews) Sunday, January 08, 2012

I am very pleased with the easy installation and quality truss rodss

short scale telecaster

By Nikos Taliadouros from Athens Greece
(Customer's Reviews) Friday, December 30, 2011

I have used your hot rod truss rods for more than ten constructions and repairs during the last two years. It works perfectly both in guitars and basses. Highly recommended. Greetings from Athens. Happy new year.

two way truss rods

By jungle guitars from goa india
(Customer's Reviews) Saturday, December 03, 2011

great quality but the depths of these rods are a little to deep be careful if your planning on a skinny neck would like to see these rods with a flat bar on the top rather than round to decrease the depth of the slot needed

Love these rods!

By Chris Thomas from Elizabeth, PA
(Customer's Reviews) Wednesday, November 23, 2011

I used to make my own 18" truss rods. I bought a couple of 6' stainless steel rods. I bought right and left handed taps and dies. I had my godfather make some anchors with right and left hand threads. They work great. But, it's a lot of work to cut your own threads and Dremel for the achors. Not to mention welding my own 1/4" hex adjusting nut.

These Stewmac rods are fantastic. Make sure you buy the router bit specifically designed to fit these rods. They go in soooo easily and the strength and evenness of the curve is great. I don't make truss rods any more. There's no need when they cost less than $16.

Works Very Well

By The Lefty Luthier from Spring Branch, Texas
(Customer's Reviews) Friday, October 07, 2011

A very powerful adjustment. Suggest full bedding with compliant silicon calk rather th.an just dabs at both ends as directed to minimize rattles.

one out of 2 ain't bad :$

By Adam P. from Tasmania, Australia
(Customer's Reviews) Monday, September 19, 2011

Just built my 2nd guitar using these truss rods, using a ball end allen wrench (as suggested on angle) has chewed the inside of the nut completely!! This metal in the nut must be really soft stuff, I barely got a 1/4 turn on my truss rod & an almost finished guitar is now screwed :(

Great Product

By TisDale Custom Guitars from Renton, WA, USA
(Customer's Reviews) Monday, September 05, 2011

I use the Hot Rod in all my custom guitars. It's strong, it can correct even the worst upbow/backbow with no signs of breaking. Very highly recommended.

Displaying 6 of 10
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Shown on page 72 of our latest catalog.
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