About the D'Addario NS Pro Guitar Capo:
 
Designed for standard electric and acoustic 6- or 12-string guitars, the Pro Capo assures buzz-free, in-tune performance at any fret. A micrometer adjustment mechanism allows you to dial in the exact tension needed for clear ringing notes without excessive force in any position on the neck. This greatly reduces the need to retune your guitar during and after capo use. The sleek aircraft grade aluminum construction can withstand the toughest playing/touring schedule while adding negligible additional weight or obstruction to the instrument. Available in additional finishes.