Magnetic Ferrofluid Liquid Display Bottle: The Ferrofluid magnet display bottle is bottle that the inner black Ferrofluid can in novelty and fascinating way and turn into various shapes when magnet is close, change by the magnet controlling. Easy to Control: The magnetic ferrofluid which is easily to operate by the magnets(NOT included), you can control the fluid by moving the magnets to close or away, up or down, make it turn into various shapes as you like, or to control dancing in the bottle, perfect desktop decoration for your , home tables and . Stress Relief Toy: The black ferrofluid bring you to mystery world, change their shape by control the magnets speed or force, combination of magnets to control it, help release adults and teens daily stress & . Science Toy: The Ferrofluid bottle well displayed the fluid movement by participate and playing, which is attractive and popular for , teenagers, let know the ferrofluid perfectly and also suitable for window display or desk decoration. Great : The ferrofluid display bottle is great for & adults as birthday , Christmas , housewarming which is suitable for , family, colleagues, friend and hobby collectors.