DESC: HP's new Smart adapters enable a new level of compatibility across the HP Business Notebook lineup providing a worry-free user experience. HP's Smart adapter option kits include a "legacy dongle" so that they are backwards compatible with older HP notebooks, providing an unprecedented level of commonality. 135W Smart AC Adapter is optimized for 120W notebooks and higher, as well as for basic and advanced docking stations. Included dongle must be used for compatibility with legacy HP Business Notebooks and Tablet PCs.