The bearish Crab pattern example in the above chart shows how price reacts near the Price level of swing/pivot point D. In the above example, AB retraces to 53.7% of the XA leg and then declines towards 70.1% of AB leg. Price then rallies from C form the CD leg which is an extension of 162.6% of XA leg and 389.3% of AB leg.
An observation from the above bearish Crab pattern does not meet the Fib levels to the dot. However the overall price action and structure makes it a qualified bearish crab.
After identifying the crab pattern, a short position is taken at the low of the price at swing/pivot point D with stops at the high. The targets are 61.8% and 127.2% of the CD leg, which price manages to reach.
One of the shortcomings of the Crab pattern is that it is a bit complex. Combine this with the fact that the stop loss levels needs to be adjusted can mean that traders will view the stop levels differently. The harmonic crab pattern is best to use along with other trading methods, especially horizontal support/resistance as well as trend lines.
Some traders also prefer to make use of oscillators to confirm the bearish momentum especially when price is trading the Price swing point D