RCT Synthese PACKAGE 2.The reaction block allows synthesis to be carried out in round flasks at temperatures of up to 180 °C. This system ensures optimal heat transfer from the heating plate directly into the medium. Uniform mixing is also guaranteed because there is no interference to the magnetic field from the aluminium blocks. The PTFE coating prevents burning and ensures that working with the system is safe. Reaction blocks are available in three standard sizes. These can be adapted to various flask sizes using the appropriate inserts.