The patented truss rod is exposed flush to the rear surface of the neck and
is easily accessible for instant straightening adjustments without removing
any parts. This 2-foot long, 1/4 inch square, black stainless steel truss
(patent number 4,953,435) will pull or push from the rear, compressing or
expanding the underside of the neck. One or two twists of the truss nut
(shown in the picture) under the belt-hook using the curved accessory
wrench will alter the fretboard profile, removing any bow if tightened, or
any arch if loosened.
It acts as a stable counterforce to the pull of the strings, and is preset
straight before shipment. Any later adjustments to fine-tune the playing
action should be made here at the truss, as a straightened neck will usually
bring all the other adjustments of the original setup back into line.
Greg Howard demonstrates how to make easy routine truss adjustments