Does it fit square shape bathtube?

Hi Emilie, Thank you for your enquiry. The Baby Dam is suitable to fit all standard size baths. Dimensions for this product are: 65cm (Width when flat) x 27cm (D). For further information on this or any of our other products available, if you follow the link https://www.babyonthemove.co.nz/store-locations/ this will take you to our online store finder. Here you can find contact details for your nearest Baby On The Move Store where one of our team experts will be happy to assist you in your product search and help answer any further questions you may have. We hope this has helped with your query.