The 183C PRO is also called Version 2, which reportedly has the following new features that are different from the [url=https://app.astrobin.com/equipment/explorer/camera/6436/altair-hypercam-183c]original 183C[/url] variant: [list] [*]Real-time Temperature sensor [*]ROI (Region of Interest) for cropped higher speed solar, lunar and planetary imaging [*]4K Mode (cropped) [*](possibly) additional internal memory [/list] It should have something like "ALTAIR HYPERCAM 183C PRO 4GB" printed on the side.