Tsa'i Revive is purely made from the dried flowers, leaves and stem of the sideritis raeseri plant. It's also known as mountain tea. This natural caffeine-free herbal tea is packed with antioxidants that help to fight cold and flu. It's a natural anti-inflammatory that enables your body to heal, reduce pain and aches. It is also believed to be a mood booster. This humble tea has a sweet, floral and earthy flavor.