I don't like this unit!! It is so top heavy that it falls over if you take your hand off of it.  There is no locking mechanism to hold it into place if you take your hand off of the unit. BEWARE!!!! The only way to balance it is to fold it back over. This is extremely inconvenient if you need to pause and then resume vacuuming. Shark didn't think this one out very well. Very bad design.