As I know it is the Trailing Stop indicators: Volatility Trailing Stop.
It was converted to MetaTrader 3 from Omega or Metastock or from some book. They did it for MT3
here and received 13 indicators. And they wanted to received just one instead of these 13 and convert it to MT4. So they did it.
I dont know how to use it exactly. May be Alex knows as he posted it here for MT4.
All that I know that they use it together with S&R and Fibo lines to estimate the market condition and sometimes for the trading.
An other set of indicators is attached.