The VP 741ABZ and VP 743AZ Series are specially designed for use in combination heating and stirring. The design minimizes drag on the Tumble Stirrer motor due to Eddy currents generated by the changing magnetic field. This allows a broader range of V&P’s Stirrers, including those with less powerful motors, to be used in combination with heating. The Heating Blocks come with an SBS Adaptor Base made of Mica that is attached to the Heating Block’s underside. This Mica Base provides heat protection for surfaces below the Heating Block and facilitates its use on SBS-configured locations. The Mica is safety rated by UL laboratories as UL 94VO.