I bought this product quite a long time ago. It basically has 4 sides that is all you need for naturally beautifully, neat and healthy looking nails. It comes conveniently as one block, so you don't need to carry 4 different nail buffing/shaping filers like they use to be when it was old school ;). I like that each side has a number to it so you know which order to do your nails in. I've had this block forever and it still works very well. The block shape is also a really nice form to hold, as if gives your hand the perfect grip to buff your nails perfectly. As I have quite brittle, thin nails, I try not to use the remove ridges part too long, but it really works effectively for people who have slight ridges in their nails.