The D'Addario NS Tri-Action Capo is a revolutionary capo designed for buzz-free, in-tune performance at any fret. The patent-pending Tri-Action geometry reduces the force required to open and close the capo, and applies even tension regardless of neck profile. Combined with the micrometer tension adjustment and direct horizontal pressure, the Tri-Action Capo virtually eliminates pulling the strings side to side and the need to retune during use.