This rollerball no longer available but is very similar to the popular BigTrack. It has a much larger ball and only one button, which is mounted on to the front. Because of this the button can get hit accidentally and the pupil often ends up clicking everything everywhere. The lack of a second button means right clicks aren't easily possible, but this shouldn't affect too many users.
The exceptionally large ball is useful for visually impaired and the youngest users, but the whole thing is very light and tends to move around if not fixed down. There is a significant gap between the ball and the casing, and I have found that grime can slip through this and accumulate under the ball, making the whole thing potentially less accurate and rather tricky to use..
Having said that, this is a very popular rollerball and I've seen it used well in many schools.
Unfortunately this product has been discontinued and is rather difficult to get hold of. Maybe you can find it on eBay y if you keep an eye out for it - maybe not! If not I would suggest that you try an alternative rollerball such as a BigTrack or a Inclusive KidTrac.
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