Stirrers are the tools of a stirrer, stirring apparatus, stirring vessel or stirring unit. They are usually interchangeable. In the laboratory, the following terms, among others, are common: – Magnetic stirrers: stirring rods, “stirring fish” in rod, dumbbell, triangular, egg, or cross form. – Propeller stirrer – Stirrers with interchangeable stirring blades (cut or pointed ends) – Turbine stirrers (different designs from slanted blade stirrers to disk stirrers) – Jet mixers (maximum speed targeted to the bottom) – Centrifugal stirrers (blade stirrers with blades that can be folded in towards the shaft, and which project outwards due to centrifugal force. Allow insertion into narrow openings of flasks) – Anchor stirrers (see above) – Half-moon stirrer: blade stirrer close to the bottom for round-bottom flasks (also in hinged design) – Fan stirrer (like grid stirrer) – Dissolver (like toothed disk stirrer) – Stirring coil (spring spiral instead of blade, radially conveying like disk stirrer) – Visco Jet (2 or 3 tangentially arranged “bottomless” buckets acting as nozzles) – ruvastar (3 tangentially arranged deflection arcs)