Aluminum heat transfer block, 9594-12 for use in place of a glass sand bath in Microscale experiments. Offers excellent heat transfer and will not interfere with magnetic stirring. Block has four holes for vials and one hole for thermometers. 9594-16 for use on top of stirrer-hot plate to effect better heat transfer. Block has three bowl shaped-recesses, one 20mm straight-thru hole, one deep bowl-shaped hole, and one hole for a thermometer. 9594-08 auxiliary heat block for use with 3mL and 5mL conical vials.