My hotplate is 135 mm in diameter. Do I need an adapter to use Heat-On?

Heat-On blocks have a 145 mm diameter recess in the base to locate onto the hotplate.

If you have a 135 mm round hotplate, you have the option of purchasing an adapter plate (part number RR61085) if you would like Heat-On to fit more tightly onto your hotplate.

heat on adapter for 135 mm hotplate