I don't have a 12-string guitar, but I bought the 12-string capo for my classical guitar, as the Kyser 6-string capo was inadequate, and could barely grasp all the strings above the 3rd fret. With this, I can capo pretty much all the way up the neck. I highly recommend this (and at the same time, I don't recommend the 6-string capo at all, for anyone).