Shubb Standard Capo - Polished Nickel
C1 - for steel-string guitars (fits most acoustics and electrics)
The Shubb capo is BY FAR the best at not creating tuning problems. Its soft, resilient rubber is specially designed to work just like a fingertip, so it doesn't bend the strings over the frets. Its closing action is just like your hand, so it doesn't pull the string off center. As a result, no re-tuning is necessary!