- Generic slim 5v 2amp power supply - Compatible with all Yealink T3X T4X and T5X phones. - ETL and FCC certified - 1.8M (5.9 ft) flat cord - As long as the phone requires 5v and 2 amps or less the power supply will only provide the power the phone requests. So if the phone requires 5v and less than 2 amps this power supply will work.