The Butterfly pattern , is a harmonic pattern discovered by Bryce Gilmore using his Wave trader software program.
The pattern structure was further refined using specific Fibonacci levels by Scott Carney which he outlined in his book 'The Harmonic Trader', published in 1998.
The Butterfly pattern must include an AB=CD pattern to be a valid signal. In general, the AB=CD Pattern will possess an extended CD leg that is 127.2% or 161.8% of the AB leg.
Use the link to the Butterfly pattern tutorial below for further details regarding the structure of the Pattern.