A:AnswerHi Chris, there is no difference between the two as they are the same model. The third camera model in the DSCRX100 series is called DSCRX100III, DSCRX100III or DSCRX100M3. Thanks_Mitch
A:AnswerHi mike, it is best if you refer to our official marketing specifications sheet for this camera to avoid confusion. Please visit the link provided for the specifications: https://docs.sony.com/release//specs/DSCRX100M3_mksp.pdf Regards, -Mark