All I did charge the battery for 15min and see the main unit powering, can see blue light and white light. Unit comes with a battery and a charger as seen. I do not know much about such a unit but did sell a similar devices before. The item "WELCH ALLYN PANOPTIC OPHTHALMOSCOPE 11820 With11720 & 23820, IN CASE, AS IS" is in sale since Wednesday, December 06, 2017.This item is in the category "Business & Industrial\Healthcare, Lab & Life Science\Medical Specialties\Ophthalmology & Optometry\Ophthalmoscopes". The seller is "minenowurs" and is located in Bartlesville, Oklahoma. This item can be shipped to United States, Canada, United Kingdom, Denmark, Romania, Slovakia, Bulgaria, Czech republic, Finland, Hungary, Latvia, Lithuania, Malta, Estonia, Australia, Greece, Portugal, Cyprus, Slovenia, Japan, Sweden, South Korea, Indonesia, Taiwan, Thailand, Belgium, France, Hong Kong, Ireland, Netherlands, Poland, Spain, Italy, Germany, Austria, Israel, New Zealand, Singapore, Switzerland, Norway, Qatar, Kuwait, Bahrain, Croatia, Malaysia.