22mm: 22mm pushbuttons and selector switches have gained in popularity with the introduction to IEC standards in North America. These operators are very cost effective compared to their 30mm counterparts.

30mm: 30mm NEMA rated pushbuttons and selector switches have been the standard for many years. They are more robust than their 22mm counterparts and should be considered if the panel will be mounted in a high traffic area or where damage is more likely.