Model differences
PETKIT Purobot Ultra vs Max Pro 2: bag packing, camera and fit
PETKIT’s Purobot Ultra and Purobot Max Pro 2 are both enclosed rotating sifters for compatible clumping litter, with app-connected cameras and no published household cat-count rating. The choice is less about an “AI” label and more about how much camera movement and waste-bag automation you want, how much space you have, and whether you accept a person-attended bag-packing routine.
The biggest daily difference is the waste bag
The Ultra’s 10-liter waste bin uses PETKIT’s auto-packing module: it seals a filled liner and advances a new one from a proprietary refill ring after you take the sealed bag out. The steps are not hands-free from a distance. Its manual says to start packing at the device’s OLED panel and stay beside it; after removing the bag, you confirm the new-liner feed at the controls. If you want to avoid touching loose waste but can attend that sequence, this design has a practical advantage. If you want a simple waste drawer with a pull-out liner and no proprietary refill ring, the Max Pro 2’s 8-liter drawstring bag compartment is simpler. Neither routine removes the need to empty and inspect the bin.
Camera movement changes the view, not the need for judgment
The Ultra camera rotates to look outward and then toward the litter chamber; PETKIT also lists a two-way audio feature. The Max Pro 2’s P9904 camera is fixed, with a 210-degree field-of-view spec and one-way audio. Both listings include individual-cat identification and health-oriented alerts, but the company’s profile count is not a rated cat capacity and app events do not diagnose disease. The Ultra manual and Max Pro 2 manual connect full video playback to Care+ service terms. Either machine can be a poor fit if you do not want a camera in that room; compare a camera-free sifter rather than buying for the alert language alone.
Capacity claims need careful interpretation
The Ultra has a 70-liter cylinder and 10-liter waste bin; PETKIT says the bin can hold one adult cat’s waste up to 20 days in lab conditions. The Max Pro 2 has a 76-liter chamber and an 8-liter bin, with an “up to 17 days” single-cat estimate. These are maximum use-time statements, not a manufacturer rating for how many cats can use either machine or a promise that the box needs attention only at that interval. Actual waste volume, refill rings, humidity and the cats’ routine matter. Empty or pack from the unit’s indicators and your own inspection, not the single-cat headline.
Fit, litter and safety rules still decide suitability
Current manufacturer specs list the Ultra at 20.94 inches wide, 32.20 deep and 24.09 high, with a 10.43-inch entrance height; the Max Pro 2 is 25.86 by 21.18 by 23.74 inches by the U.S. product page, but its manual reverses the first two dimensions without labeling their axes. Both need a hard, level location and wall clearance. The Ultra is longer front-to-back; the Max Pro 2 has a wider body and lower entry. Check the exact placement and the cat’s real approach rather than assuming one is the “compact” choice.
Both use compatible clumping litter and the manufacturer’s particle limit of no more than 12 mm long or 3 mm wide. PETKIT lists the Ultra for cats weighing 3.3–22 pounds and prohibits cats younger than six months or under 1.5 kg; the P9904 manual has the same age/low-weight prohibition. That conservative age and weight boundary matters more than camera features. Neither product page gives a household cat-count rating, and two-box bundles do not change that.
Which one is easier to own?
Choose the Ultra if you want camera motion between the room and box, a larger bag bin, and powered bag sealing/refill—and are willing to use PETKIT rings and attend each pack cycle. Choose the Max Pro 2 if its fixed camera and drawstring-bag handling suit you better, or if its 76-liter chamber matters more than a larger waste bin. In either case, first binding in the app is required, camera history may be subscription-limited, and cylinders still need manual cleaning. A package’s bonus litter and odor refills do not change these operating facts; compare the exact base and supply-bundle SKUs before choosing. See the full Ultra review, its two-unit bundle review, and the Max Pro 2 review. Use the official Ultra listing, Max Pro 2 listing and each product’s current manual to confirm the configuration and care steps.