False star rating!
The reason this trimmer has such a good rating is due to the fact that Amazon has linked reviews to a completely different product to this trimmer.  Earlier reviews have also complained about this issue, but the fact is that the supposedly great rating hasn't been changed.  My review:  while the trimmer makes noise when turned on, it doesn't clip the hairs in its path, even after multiple attempts.  Also as noted earlier, there were no instructions included in the packaging about how it should be cleaned.
Rating: 2 stars