RSI is a momentous oscillator used to identify trend reversal. Invented by Welles-Wilder-Jr, it calculates the strength of a stock trend and helps to predict their reversals. RSI PBB is pull back buy setup which indicates, once the RSI turns its tail upside after taking support from zone of 45-55 levels, target is previous swing-high of RSI which was 75 or previous swing high-of-prices(200).