Okw dials for roundwing knobs transparent with graduation scale okw a 44 23 020 the okw a 44 23 020 dial for roundwing knob 23mm transparent with graduation scale has been manufactured with pc ul 94 hb material and can be fitted with ease onto a 23mm roundwing knob okw a 44 23 020 dial for round knob 23mm transparent w bk graduation