Manual operation. Waterproof, no battery required. Perfect for various hairstyles from thick to thin, short or long, and no matter wet or dry, even to groom hair of your petsTaking shower with this soft shampoo brush makes your hair and scalp cleaner than before. A soft and high-quality hair brush provides you an enjoyable washing experienceMassaging your scalp in the shower to ease itchiness and promote blood circulation. Getting a relaxing massage at home and every time you wash your hairErgonomic design perfectly fits in your palm and is easy to hold. Only 1.9 Oz, lightweight and stores easilyExcellent scalp massager is suitable for who has long and manicured nails, you won't damage your manicure during washing hair anymore