Truss rod

Guitar neck part / From Wikipedia, the free encyclopedia

The truss rod is a component of a guitar or other stringed instrument that stabilizes the lengthwise forward curvature (also called relief) of the neck. Usually, it is a steel bar or rod that runs through the inside of the neck, beneath the fingerboard. Some are non-adjustable, but most modern truss rods have a nut at one or both ends that adjusts its tension. The first truss rod patent was applied for by Thaddeus McHugh, an employee of the Gibson company in 1921,[1] though the idea of a "truss rod" appears in patents as early as 1908. [2]