These mattresses are made for us to be a suitable depth for our childrens bunk beds, midsleepers and highsleepers. They are the options with all of our childrens beds including bunk beds, midsleepers, low bed frames and storage beds. Every bunk bed and high bed has it's own safety depth for the mattress. With our bunks and high beds the mattresses offered will be below the safety line. If you are ordering a bunk bed or any other childrens bed, if you select the mattress alongside that bed they are at a discount multi-buy price. There are single mattresses, and small and full size 4ft6 double to fit our triple sleeper bunk beds.