The Sunwayman M30R and M60R are both extremely high output lights that push the boundaries of flashlight performance. The two lights are functionally identical, and they even have the same max output of 800 lumens. The difference between the two is the power source. The smaller M30R uses 3 CR123 lithium primary batteries. The bigger M60R utilizes 6 of the CR123 lithium batteries. The M60R can be thought of as twice the flashlight compared to the M30R, while still having the same output. The M60R uses double the batteries, and has double the run time compared to the M30R. Which light is best for you all boils down to how big of a light you want, and also how long you want the light to run. Both lights are perfect for the person who wants a mega output light with super high quality in manufacturing. Sunwayman is known for their quality and craftsmanship, which means no matter what light you choose you will be getting one of the highest quality lights available today.