The mechanism that clips on
The mechanism that clips on the shaft is a fixed size. A few small rubber rings are included with the objective to adapt for smaller shafts. These rings are nowhere close to working - the device is unstable on the shaft. They must stretch over the grip and will likely break. Also, they are nowhere thick or wide enough to keep the device secure on the shaft. The laser line does not seem as long as demonstrated in the website videos. The concept is good; implementation is rather poor.