Cumrige M4 + M5 Double Set review

Two machines, not a single larger litter box

The M4 + M5 offer is one exact U.S. bundle SKU, M4-5-FBM, containing two separate Cumrige machines: an enclosed M4 and an open-top M5. The image and product title show both designs, but the package does not turn them into a shared drum, larger litter chamber or automatically synchronized system. Think of it as two stations to place in different rooms or on different floors. Keep ordinary access to both and plan to maintain each drawer separately.

This pair is unusually useful if the household genuinely needs both kinds of entrance. M4 is the covered front-entry rotary model; M5 leaves the litter bed open from above. A cat that prefers a shelter-like box may use one while a cat that rejects an enclosure can approach the other. The flip side is that a household wanting a consistent experience gets two different entry styles and controls to manage. Do not expect both cats to share the same preference or both units to behave as one connected appliance.

Compare the two waste and fit routines

M4 has a 15-liter sealed drawer and its maker says a single unit can serve up to three cats, with the interval shortened as use increases. Its FAQ says cats around 11 pounds or under are the more comfortable enclosed fit. M5 has a 10.5-liter drawer and is described for two to three cats; its manual’s age and weight guidance is stricter than the product page’s headline range. Neither box’s volume or capacity should be added to produce a six-cat rating. These are separate stations with separate containers, and Cumrige does not give a numeric household rating for the combination.

Both use clumping litter and offer app control over 2.4 GHz Wi-Fi, but the best documented litter advice differs. M4’s FAQ favors low-dust clumping bentonite and suggests allowing clumps to firm before a cycle. M5’s product specification lists bentonite, mineral and mixed litter and excludes tofu and crystal. If choosing one blend for both, verify it against the stricter M4 recommendation rather than assuming one machine’s list transfers to the other. The bundle page does not establish that one account or app screen coordinates their operations.

Where the second machine helps

Two boxes can make sense when the home layout has separate cat zones, a long route between floors, or cats that avoid sharing a station. The M4 + M5 bundle gives a covered and open-top choice in one purchase rather than two copies of the same box. It can also let an owner compare which entry shape a cat uses, while retaining a manual tray during transition. That is a practical use case—not proof that the package improves acceptance or changes a cat’s habits.

There is a real cost in space and follow-up. Measure two locations, two power routes, the drawer pull-out clearance and a safe path around each unit. You will need to check two fill levels, two waste bins and two cleaning cycles. If the household only has room for one machine, compare the standalone M4 and M5 by entry style and cat limits instead of buying a package whose second station cannot be placed well.

Who should choose another bundle?

M4 + M5 is best for a buyer who wants exactly two stations, values both enclosed and open-top access, uses clumping litter and is ready for separate maintenance. Its package SKU is useful when checking the offer; the product title alone is not enough to confirm contents. Compare M2 + M4 if two enclosed models are more appropriate, or M5 + E if two open designs are preferred. The bundle’s maker language about multi-cat use should not be treated as a combined numeric rating.

Manufacturer references: M4 + M5 product page (bundle SKU M4-5-FBM); see also the individual M4 and M5 pages for model-specific limits.