moveable shelving unit

it's not as good an idea as you might think - I used to be a mover and I have seen some "interesting" things... that might hold up for a while - but it will inevitably fail (that bottom shelf will buckle) and it WILL be when you're not around.. if you HAVE to do something like this - go buy (or build) a good bookcase.. IMO, that one is a flimsy POS