London Baby Swim operates a double nappy system for all babies and toddlers until they are toilet-trained. The double nappy system is a disposable or re-usable swim nappy underneath a Happy Nappy (neoprene nappy), which should fit closely enough to form a tight seal around the waist and thighs. Disposable/reusable Swim Nappies are available from supermarkets and drugstores. Children do not need to wear anything else apart of the double nappy system. Children wearing swim trunks, swimsuit, Eczema Suit or similar are welcome, however they will still have to wear the double nappy system underneath if they are still not toilet-trained.