Classi Concentric Collet Wing Knob Set 21mm black
Classi collet knob set with indicator lines. The bottom knob has a diameter of 21mm without wings and 25mm with wings. The inner knob has a black cap with an indicator line and the body has also an indicator line to have nice view of the positions. Fits on 6mm, inner 3mm and 1/4" with inner 1/8" as well.