the present invention relates to the technical field of fluid heater devices , and more particularly to an electric immersion heater for use in electro - plating , metal preparation , finishing applications in the electronics industry . the invention more specifically provides a new and improved electric immersion heater design that includes , in combination , a unique flexible cable structure enabling small diameter coils which , in turn , are mounted on a support frame structure . this provides an inexpensive heater assembly that has optimum heat transfer capability in liquid treating mediums .