Replacement knobs for Ikegami TM and HTM series CRT Broadcast monitors.  They will work with most models circa 1992 and later.  Confirmed models include:

TM10-17R, TM14-17R, TM20-17R, TM24-17R, and TM32-17

TM14-20R, TM20-20R, and TM20-30R

TM14-80R, TM15-70R, TM20-80R, and TM20-90R

HTM-1005R, HTM-1505R, and HTM-2005R

HTM-1517R, HTM-1907R, HTM-1917R, and HTM-1990R

This model is optimized for a 0.4mm nozzle & 0.8mm layer height.  It should be printed right side up with no support.  You may need to resize the model slightly (depending on the printer/filament used) to get a snug fit on the stem.  I hope to update the design for a 0.2mm soon, which will should give better results.