The Phase One power supply can be used with a Phase One 645 AF or DF camera.This 645 AF/DF power supply offers DC 9V, 2A (Ampere)The inner centre pole has positive polarity, while the outer pole has negative polarityThe DC plug is 4.75mm longYou can insert the power plug at the bottom of the camera body by removing the protection plugThis power plug provision is located beside the battery bay lock