This is a 1X C-mount photo adapter for AmScope microscopes which use the CX photo-port, including some SM series stereo microscopes, and newer T490 series microscopes. This adapter allows cameras with large image-sensors (1" class) to be used without vignetting. Features & Specifications : Power: 1X Camera Sensor Compatibility: 2/3" to 1" Compatibility: SM745T (not V203 or V331), T490 Camera Mount: C-mount(1" / 25.4mm diameter) Manufactured under ISO 9001 Quality Control Standards Warranty: 1 Year