Shubb FS Fifth String Capo for Banjo
This was the product that got it all started for them back in 1974, and to this day it's STILL the only fifth string capo worth putting on a banjo. It operates on a lever principle, not a spring, so it provides sufficient pressure to fret the string without muting the tone. It slides on a slim, dovetailed bar which mounts flush to the neck, making it sturdy and unobtrusive.