First off, I had ordered another weed whacker like this one, but the serrated edge was longer, which my son was able to break off with no problem. I like this one better, because the serrated edge is shorter, and seems to be more sturdy. If you use it correctly by swinging your arm back and forth, without twisting your back or bending over a bit, it keeps you from having aching muscles the next day. It is very effective on weeds, but not as well on grass, because weeds have wider stems and grass is much thinner. So, if you're going to use it on regular grass in your yard, you're better off having a lawn mower. So I would call this a weed whacker instead of a grass whip. I love mine, so I do recommend it, especially if you're trying to go green.