“ Ah yes, the Park Tool CM-5. 3 Cyclone Chain Scrubber. Because apparently humanity looked at a dirty bicycle chain and decided what it really needed was a tiny blue washing machine filled with industrial sadness. For just under twenty quid, you too can experience the thrill of dragging your chain through a plastic aquarium of black sludge while pretending you’re a professional mechanic in the Tour de France rather than a middle-aged man in the driveway muttering about “drivetrain efficiency. ” To be fair, it does exactly what it claims. The rotating brushes, solvent reservoir, magnet, and sponge system genuinely clean the chain extremely well. Unfortunately, it also reveals horrifying truths about your bike maintenance habits. After one use, the liquid inside looks less like degreaser and more like something recovered from the engine room of a Soviet submarine. The marketing proudly states it “extends the life of expensive drivetrain parts. ” Which is wonderful news, because after buying modern cassettes and chains, you’ll need every financial advantage you can get. Highlights include: Hundreds of rotating bristles aggressively interrogating your chain. A magnet at the bottom collecting metallic particles like some tiny scrapyard crane. A “wicking sponge” whose job is essentially to whisper “please stop dripping on the patio. ” The best part is the transformation in personality it causes. One minute you own a bicycle. The next minute you are explaining lubrication intervals to trapped relatives at family gatherings. Five stars. My chain is now cleaner than my conscience.