- Turn your hotplate into a heating mantle - Flexible modular system - Range of sizes available up to 500ml - Cleanest and safest way to round bottom flasks The Stuart range of heating blocks have been developed in conjunction with DrySyn to provide the best possible solution for heating round bottom flasks. Combined with the Stuart range of undergrad hotplates and hotplate stirrers, the Stuart heating blocks provide the cleanest and safest method for synthesis for single of multiple reactions, whilst giving equal or better heating performance than silicon oil.