Merck 171202 Thermoreactor Tr 620 2 X 12 Holes İn 2 Heating Zones. In Each Zone Temperature And Time Can Be Controlled Separately. 5 PreinMerck 171202 Thermoreactor Tr 620 2 X 12 Holes İn 2 Heating Zones. In Each Zone Temperature And Time Can Be Controlled Separately. 5 Prein, Merck171202.0001