Polypropylene and Polyethylene are still in the development and experimental stage (1963), but they will undoubtedly be introduced into the Royal Navy at some future date because they will float.
IPolipropelina kunye nePolithelina zisekwinqanaba lokuphuhliswa nokuvavanywa (1963), kodwa ziza kwaziswa kuMkhosi wamanzi kwixesha elizayo kuba zona ziza kudada ngaphezulu kwamanzi.