The Booster Vibrator is a module of the Boosting locomotion; it provides a particular functionality for its parent Booster. If it is disabled or removed, then the relevant boosting functionality will behave as by default. Most modules can optionally affect change globally (for both hands' Boosters). Booster modules can also depend upon conditions specified by their dependencies settings.
On this module you can tweak the vibration intensities for controller haptics while boosting.