MAKITA | AVT Rotary Hammer 1-9/16" | HR-4013CMakita HR4013C 1 9 16" AVT Rotary Hammer. Makita's Anti Vibration Technology (AVT) is a synchronized, three component system that more effectively reduces vibration resulting in a low 5m s It has a Lock on or trigger activation in "Chipping Only" mode with a push button start stop control for more convenient operation. The Electronic Controller provides Constant speed control automatically applies additional power to the motor to maintain speed under