A damper assembly for a vehicle suspension system includes a primary damper and a secondary damper. The secondary damper is coupled to the primary damper and includes a housing and an annular piston. The housing includes a sidewall that partially surrounds the primary damper, and the volume between the sidewall and the primary damper defines a damping chamber. The sidewall defines a plurality of apertures. The annular piston is positioned within the damping chamber and slidably coupled to the sidewall. The primary damper provides a base damping force and the secondary damper provides a supplemental damping force that varies based on the position of the annular piston along the housing.