Whisker says both models weigh the same and have the same depth. To me, this new modelfeelssignificantly smaller—in a good way. It doesn’t look as bulky, and the design is much sleeker. The Litter-Robot 4 is a few inches narrower, though the entrance for kitties is way larger, almost 16” x 16”, a full five inches wider than the previous version. Not only that, but the step is slightly lower to the ground and the box entrance itself is about an inch lower, making it easier for cats to climb in.
The waste drawer is also larger and better contains smells. Again, at first glance this fooled me. Because the unit’s base is designed to take up less space (yay!), the waste drawer looks smaller (why?). Au contraire! The drawer holds just as much as before because it’s deeper. Whisker offers an add-onOdorTrap™ System podthat can help reduce any stinky scents, though we’ve had no issues with smells thus far.
Another huge design improvement? The buttons are on the top of the bot instead of at eye (and nose) level with the litter. Instead of squatting down to hit reset after cleaning the waste drawer, I just lean in a bit (if you’re 6’7” this doesn’t matter much, but it does to me!). I also love how the button panel lights up to indicate what’s going on with the machine. Is the drawer full? Flashing blue light. Is there a cat inside? Red light. Did I successfully put it into sleep mode? Purple light (yes).