As we all know when we trim around cement, bricks, or stone the line breaks. So I bought this trimmer head so that we can not only trim around stone without a problem but in some intances we can also clean stone with this head. It is a steel wire brush and not easily broken nor damaged. We have used it for several months now and I will say it works wonders and would like to buy another as it is well worth the money. I would definitly recommend to my fellow tool people.