I need to replace the blue conical part inside the stirrer guide. What’s the part number? The blue conical stirrer grip inside the Reactor-Ready and Lara stirrer guide, which we refer to as a ferrule, is included in the following spare part pack: RR121064: Stirrer Guide Ferrule & Shaft Seal B24 10 mm As you can see, RR121064 includes the shaft seal (white washer with black O-ring) that sits with the blue ferrule inside the stirrer guide. It is normal for these parts to become worn/deformed with use, so it’s important to regularly check them and replace them if there’s any sign of deterioration. RR121064 is included in the RR121150: Reactor-Ready Maintenance Kit. (For more information, please refer to the separate FAQ entry ‘How can I maintain the performance of my jacketed lab reactor? What are maintenance kits?’.) For the larger Reactor-Ready Pilot stirrer guides, the equivalent part numbers are: RR121138: Stirrer Guide Ferrule & Shaft Seal B34 16 mm RR210100: Reactor-Ready Pilot Maintenance Kit