A constructional unit for a drivetrain of a motor vehicle includes: at least one clutch arrangement configured to decouple an internal combustion engine from the drivetrain, the at least one clutch arrangement having at least one clutch element; a speed-adaptive vibration absorber apparatus, configured to reduce vibrations in the drivetrain with at least one damper mass deflectable along a deflection path; and a limiting device configured to exert a force on the at least one damper mass that limits the movement of the damper mass. The limiting device is further configured, for limiting the movement of the at least one damper mass, to be actuatable by the at least one clutch element.