I just learned about these shampoo brushes recently and while I was skeptical, only after a week in, my scalp and hair are noticeably better and continue to improve.I have a mild case of seborrheic dermatitis and would get randomly red welts with scaley/dandruff-like patches on my scalp especially around the hairline. I also had a pretty itchy scalp. I just thought I had to live with it but it appears it may have been caused by not rinsing my hair properly and allowing bacteria to grow on my scalp. Enter the shampoo brush...The brush helps massage the scalp, distribute shampoo evenly and most importantly, scrub away scales and left over shampoo. As mentioned, only after a week, the scales and red welts are gone, my hair is smoother and far less greasy. Amazing results for under $5.As for the tool itself is pretty basic but feels solid and I can't imagine it breaking even with years of use. Again, well worth the $3-5.If I had one problem it would be there aren't really any instructions and I couldn't find any good directions online for similar brushes. Here's what I do which seems to be working...1. Wet hair2. Lather hair with shampoo3. Use brush and slick back the hair from front to back making sure to get your entire scalp, around the ears and neck line4. Rinse shampoo5. Use the brush again and slick back the hair again without the shampoo to thoroughly clean the shampoo off and scrub the scalp one last time6. Rinse once moreGood luck!