Several different-sized heads are available for use with the IND50 Induction Heater:
HEAD12 - 1/2" Insertion Hole (1-1/2" outer diameter) for Glass up to 10mm
HEAD58 - 5/8" Insertion Hole (1-1/2" outer diameter) for Glass 10-13mm -- this head is included with the IND50
HEAD34 - 3/4" Insertion Hole (1-1/2" outer diameter) for Glass 13-17mm
HEAD78 - 7/8" Insertion Hole (1-3/4" outer diameter) for Glass 17-21mm
HEAD100 - 1" Insertion Hole (1-7/8" outer diameter) for Glass 21-25mm