A pile of huge boulders collapsed in my yard - it was a waterfall. There was no access for large devices and we had to get them out of there. I didn't know such wonderful little things existed until I watched some videos of huge rocks being smashed. It really works! I wouldn't believe it, but after breaking about 15 huge rocks into smaller rocks that could then be moved around, I believe and could kiss the person who invented them. That was the answer to my problem with Rock. Just a note: this gave me some rocks for my landscaping.