The Booster Pulser 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.
The Pulser will add a pulsing force to the booster's force calculation. You can tweak the force percentage and frequency, as well as set whether to pulse based on the y direction only. This is useful when combined with Automating and Relativizing to have the player automatically hover up and down.