UNUS SED LEO is a utility token utilized throughout the iFinex ecosystem. The unique name is derived from a Latin reference in one of Aesop's stories. Bitfinex customers can save money on trading costs by using the cryptocurrency. The amount of the discount is determined on how much LEO the client has in their account, and the savings are divided into three categories. Depending on whether a trading pair is crypto-to-crypto or crypto-to-stablecoin, there are variations.