The black NS Capo Pro from Planet Waves is made from aircraft-grade aluminum and is designed for use on both 6-string and 12-String acoustic or electric guitars with radiused fingerboards. With its patented micrometer adjustment mechanism, the capo can be dialed in with the perfect amount of tension needed for clear ringing notes without excessive force, resulting in buzz-free performance at every fret. This greatly reduces the need to re-tune your guitar during and after capo use. The lightweight unit features a sleek construction that can withstand the rigors of on-the-road wear and tear, while adding very little additional weight or obstruction to the instrument.