Genuine Original Lenovo PA-1900-171 ThinkPad R500 Series 90W 20V 4.5A AC Adapter Power Supply 92P1109 11S92P1109 93P5026.Lenovo Part Number: 92P1109 11S92P1109Model Number: PA-1900-171Compatible Part Numbers: 93P5026Compatible Models: ThinkPad R500 SeriesSpecifications:AC Input: 100V - 240V 50/60Hz 2.4ADC Output: 20V - 4.5A