Excellent small device, fast and discreet, with a simple breath away! A lively ball movement due to internal lingo, never stuck, always en route to somewhere, taking with it the "cage" that glides lightly wipe the ring and picks up everything in its path, well almost! No worries cables, or other obstruction, it stumbles, and it leaves for elsewhere, unperturbed, what! ... However, any relief (> 0.3 cm) is obstacle, and collection concerns only dust and small elements, of course! In short, excellent, fun to watch and work for cheap, and more!