Rationale
The rationale behind this indicator is that: when the price of an asset reaches an extreme, regardless of the trend, there is a (maybe not equal but) opposite reaction.

Settings
The default settings will not be the best for whatever timeframe you choose. I personally believe a longer than 'normal' JMA Length is best.

JMA Source: The source in which the Jurik Moving Average calculations are based off of.
JMA Length: Controls the length of the Jurik Moving Average.
JMA Phase: A lag controller of sorts. Increasing the phase increases overshoots but reduces lag, decreasing the phase decreases overshoots but increases lag.

ATR Length: The length in which an average true range value will be calculated with.
ATR Multiplier: This multiplier controls the 'width' of our envelope or our extreme bands.

Credits
@gorx1 for the improved and more accurate (?) Jurik Moving Average calculations.
@redktrader for the ATR envelope calculations.

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