I wasn't sure if this extra part was necessary, but I splurged and bought it. I cant imagine having to look at my litter robot more than once a week to add litter. I only have to change the bag and add litter once a week with 3 cats. It was so worth it.
It has a hole at the top and in the middle for the litter to come through, but they didn’t think about if the cat pees in there that it will go out the hole of where the litter comes through and run down and get the floor wet so I do not recommend this product
Pretty easy to install and get setup. Works flawlessly so far keeping litter levels ideal. Has been lasting 4-5 days before needing to refill with our 2 cats. Has made the LitterRobot even better now being able to go almost a week without any intervention
The only missing piece is there is no sensor to let you know when the Hopper is empty!