Product review (5 stars): Yes, by design- it only has 3 sides!
Dimensions are exactly as listed in the description. It is a well made, very rigid plastic pan, i.e. you won't likely be able to flex it to make it fit if it doesn't already! It fit our (standard?) opening perfectly, the dishwasher easily slid onto it and it sticks out just beyond the bottom front of the dishwasher and the lip rests just over the edge of the wood flooring as it should. For all those complaining it doesn't have 4 sides.... no, it doesn't as it is not intended to HOLD water, it is designed in the event of a leak to push the water out the front so that the leak is apparent.