Ferrofluids are stable colloid suspensions of magnetic particles of about 10 nm (magnetite, iron, etc.) finely dispersed in a carrying fluid that combines magnetic characteristics with fluidity and can be controlled by magnetic field. Ferrofluids are successfully used in ferrofluid-based seals (feedthroughs), sensors, separators, lubricants, loudspeakers, dampers, CD and DVD drives, transformers and other ferrofluid-based devices. FerroLabs' LiquidAudio ferrofluids specifically designed for loudspeakers have unique heat-transfer properties, superior viscosity characteristics and high thermostability that contribute to high quality speakers manufacturing.