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# What size cats does OnlyCat work with?

![OnlyCat flap opening dimensions](https://storage.crisp.chat/users/helpdesk/website/-/9/d/9/a/9d9a00682326c00/flap-opening_1l26w7j.webp)**Can OnlyCat be used by cats over 6 kg?**


OnlyCat is **designed for cats up to 6 kg**, but many of our customers have successfully used OnlyCat with \*\*larger cats \*\*(including cats around 8 kg; individual suitability cannot be guaranteed). Cats are [very malleable](https://www.youtube.com/watch?v=cimcqIBSc10) and adaptable, though of course every cat is different.

Every cat is unique, and larger cats may need some time to get used to the flap. Our weight guideline helps ensure smooth operation and avoids potential issues.

**If your cat is heavier than 6 kg:**
1. \*\*Before ordering: \*\*Consider the weight recommendation, but many larger cats use OnlyCat without issue.
2. **After receiving OnlyCat**:
* Try it with your cat. Customers typically report no issues with cats around 8 kg, but individual suitability cannot be guaranteed. Compare the opening with a flap your cat already uses, if applicable.
* If it doesn’t work for you, contact Support to request a return under our **return policy**: The current 30-day trial runs from delivery and is subject to the [published condition and installation requirements](https://www.onlycat.com/returns-policy/). Check the fit before permanent cutting, drilling, gluing or sealing. **No restocking fee** applies. Return shipping costs remain subject to the current returns policy. Additional fees may apply for stains or damage depending on refurbishment needs.

**Flap opening size:**

The flap opening measures 142 mm wide by 120 mm high, so your cat will need to comfortably pass through this space.




Please provide your order number. You do not have to give a reason for a return, though you may share one if you would like help with a particular issue. An operator will review eligibility and confirm instructions before you send it back. Older orders require individual review. The current website returns policy is authoritative; this article does not itself approve a return.

## Confirm fit before permanent installation

Use the [current dimensions and suitability guidance](https://www.onlycat.com/specs/). The cat passage is **142 × 120 mm** (width × height); this is different from the external frame and the opening required for installation. Weight alone does not confirm that an individual cat will comfortably use the flap. Ask Support if you are unsure, and use the installation guide and template for the opening rather than the passage measurement.