Soak your bits in an ultrasonic bath of the included Ballistol cleaning solution then give them a light scrub with the brush and you’ll have fresh looking bits.
Shaper Bit Cleaning fluid, developed by experts at Ballistol, is specifically designed and tested for use with the BitWasher to clean grime off of router bits (other ultrasonic cleaning fluids will likely work, though we can’t promise the results will be the same).
Recommend to leave bits immersed in the cleaning fluid only long enough for them to be cleaned. This generally takes ~5 minutes, but could be longer for very dirty bits. Once cleaning is complete, remove bits, brush if necessary and dry them with a rag, rather than allowing them to stay wet for an extended time. Long-duration exposure to fluids can sometimes discolor bits.
Also works great for cleaning drill bits and shop tooling that need to be brought back to life. As with anything, test first to see if you like the results.