Tracks : Track Level Meters : Peak Hold
 
Peak Hold
Pro Tools meters provide a 3 second Peak Hold indicator.
To clear a meter:
*Click anywhere on the meter.
To clear all meters, do one of the following:
*Option-click (Mac) or Alt-click (Windows) any meter.
*Choose Track > Clear All Clip Indicators.
*Press Option+C (Mac) or Alt+C (Windows).