Also known as Tetrabutylammonium fluoride hydrate or TBAF, this reagent takes the form of a crystal white or yellow solid. It is soluble in water and hygroscopic, so it should be kept in a tightly sealed container under an inert atmosphere. It is also light-sensitive so should be kept it in a cool dry place away from heat and direct sunlight – for best results store desiccate at room temperature. This chemical causes severe skin burns and eye damage.