Hi Peter, The standard dimensions of a mattresses are 90cm x 190cm, that fits in all single beds and bunk beds. Some of the bunk beds we import from overseas suppliers can use Continental or European mattress: 90cm x 200cm to be perfectly fit in. However, any single mattress can be used with our single beds and bunk beds.
Note: For the top of bunk beds we recommend Single mattress low profile which is thinner in depth and its safer and provides good and safe bed rail for kids. If you need further assistance please drop us line on "firstname.lastname@example.org", we will be glad to help you out, thanks