The U-channel Truss Rod is a strong aluminum one-way truss rod, similar to the design used by Martin for many years.
The StewMac U-Channel Truss Rod for Bass is the choice for control of beefy bass necks. Can be installed for peghead or heel adjustment.
Item specs:
Aluminum U-channel with an internal 3/16" steel rod
5mm allen adjusting nut with washer (M6 x 1.0 thread)
Width: 0.472" (12mm)
Depth: 0.400" (10.16mm)
Overall Length: 22-13/16" (579mm) (including 5mm adjusting nut)
Installation instructions included.