Extremum is a mt4 (MetaTrader 4) indicator and it can be used with any forex trading systems / strategies for additional confirmation of trading entries or exits.
(downloadable file Extremum.rar contains Extremum.ex4 and Extremum.mq4)
Free Download Extremum mt4 indicator 
How to install Extremum in forex trading platform metatrader 4?
- Extract the downloaded Extremum.rar.
- Go to “File menu” in Mt4 trading platform and click “open data folder”. Open Mql4 folder and open the indicators folder.
- Now paste the Extremum.ex4 and Extremum.mq4 files into indicators folder and restart the MetaTrader 4.
