Okw top knob marking elements pinarrow 16mm bluegreengrey okw a 11 05 006 this okw a 11 05 006 top knob pin marking element blue 16mm is a simple push on marking element that fits snugly into the top knob making the lateral screw fixing invisible while also excluding the contact with live parts it is also possible to make a subsequent replacement of the marker okw a 11 05 006 marking element arrow for top knob sky