Synonyms: (fluorosulfuric acid-antimony pentafluoride, 1:1)
Molecular Weight: 316.81
Comments: Flash Point (°F): NONE
Label Precautions: DANGER-

    Reacts violently with water
    Store under nitrogen

A medium having a high acidity, greater than that of 100 wt.% sulfuric acid. One of the common super acids are made by dissolving a powerful Lewis acid (e.g. SbF5) in a suitable Brønsted acid, such as HF or HSO3F. (An equimolar mixture of HSO3F and SbF5 is known by the trade name ‘magic acid’.) In a biochemical context ‘superacid catalysis’ is sometimes used to denote catalysis by metal ions analogous to catalysis by hydrogen ions. By analogy, a compound having a very high basicity, such as lithium diisopropylamide, is called a ‘superbase’.
Also, vuo says re Magic Acid: Dissolves candlewax... by protonating alkanes!