Natural sponge, with cotton band, This high quality natural sponge was 'harvested' by hand. After each use, it is best to clean it with clean water, then gently squeeze it and let it dry hanging freely. Please never wring out. In case of increased soiling, you can also clean natural sponges times at a maximum of 30 degrees in the washing machine or disinfect in 70% medical alcohol (isopropanol), natural sponges are not boil-proof, however.