It couldn't be easier to use our new round sphere 3 piece bathbomb moulds! They are designed to be used by hand so no need to buy an expensive bath bomb press. Simply one of the halves inside the tube, fill with your favourite recipe and then put the other half on top. Press down firmly and voila! A perfectly formed bath bomb! The best thing is that the moulds are made from PLA which is a nature-derived "plastic" type material made from corn starch so they are completely eco friendly. They are fully compostable and biodegradable so they are great for the environment. Available in several sizes. The thickness of the Saturn Ring will depend on how much you fill the mould.