I ordered a couple of these items and extra heads, and they arrived this week. I used one to clean a carboy I had purchased used and was about to trash because I could not clean the stains with the traditional carboy brush. I tried this one and it worked like a charm. The major benefit, I believe, is that I can get some force behind this brush where the traditional brush just bends. Something you might consider for cleaning plastic carboys. The head is too large for glass carboys.
https://www.amazon.com/Upgrade-Gall...45018&s=hpc&sr=1-31-spons&ts_id=15342831&th=1
https://www.amazon.com/Upgrade-Gall...45018&s=hpc&sr=1-31-spons&ts_id=15342831&th=1