4mm Allen Nut Hot Rod Truss Rod

  • 91 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

Product Details

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 91 Reviews
Displaying 8 of 10 1 2 3 4 5 6 7 8 9 10
Write a review

4mm hex

By Chad83 from Western Australia
(Customer's Reviews) Monday, March 21, 2011

Works great! i use these in all my builds.



By gabriel.v.savoie from Montr+¬al
(Customer's Reviews) Friday, March 04, 2011

It probably is the simplest truss rod to use in any guitar, acoustic or electric. It works very well, simple to use and reliable.

No pain in the neck!

By Trident Guitars from Berkley, Michigan
(Customer's Reviews) Thursday, March 03, 2011

I use these truss rods in all my guitar necks. They are easy to install and they work great. My necks are meaty and these truss rods can adjust them easily.

Good quality trussrod

By Ricardo Fonseca from SP, Brazil
(Customer's Reviews) Monday, February 28, 2011

I recommend this trussrod, works very well as expected. The 14 1/4" size is also appropriate for short scale electric guitar too, specially Gibson-like set neck guitars. Use the 18" just for long-scale guitars (25 1/2").

Good truss rods

By B Patrick from Conway, AR
(Customer's Reviews) Wednesday, February 23, 2011

I installed these into two 000 guitars. Easy installation and they are working fine.

Do the truss rod effect the sound?

By Mack Guitarworks from Hungary/Europe
(Customer's Reviews) Wednesday, February 16, 2011

Good truss rod for the beginner, because of the easy installation and routing. I built 3 of this design, but I like the original, gibson style much more. For my taste this design needs a very deep channel. If you hit the strings very hard, you can hear some truss-rod rattle from the neck. I can't figure out, how to eliminate this. I also don't like, that the fingerboard glue surface must be reduced, compared to the traditional method. I think, this effects the sound and the sustain.

I don't use any other brand now...

By B. Jesson from Chandler, AZ, USA
(Customer's Reviews) Wednesday, February 02, 2011

I used to use the martin style truss rods until I used the two-way hot rods. With the ability to adjust in both directions I don't have to worry about any curvature. The best part is if the rod gets damaged in anyway they are not too difficult to remove and replace if the neck and slot were built correctly. All my builds now use the Hot Rod truss.

Good thing I bought this one

By Steve Skinner from Kokomo, IN
(Customer's Reviews) Sunday, January 30, 2011

After finishing my last neck I noticed it has lost it's straightness in the direction away from string tension. By turning the nut counterclockwise I was able to take the curvature out of the neck in just a moment. First time I ever had a neck bow in that direction.


(Customer's Reviews) Saturday, January 29, 2011

I use the Hot Rod truss rod in all my guitars for me it is easy to install and works like a champ every time and has never let me down. I will continue to use it in all my custom builds Electric or Acoustic hands down its the best.

Thank you stewmac

By Michael Grannis from Phoenix, Az
(Customer's Reviews) Wednesday, January 19, 2011

A truly affordable product. Good size and adjust ability. Will certainly use again.

Displaying 8 of 10
1 2 3 4 5 6 7 8 9 10

Shown on page 72 of our latest catalog.
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