ATRG Extreme Catches is a technical indicator study that is used in identifying sudden price jumps exhaustions or spike bars on the activity chart. Such price spikes are usually seen at the end of a trend or reversals. An upward spike is noticed when the indicator suddenly jumps to an extreme level above the zero signal level and price is ready to reverse. A downward spike is noticeable when the indicator suddenly dips to extreme levels below the zero signal level and price is ready to reverse.