Logitech g5 is a gaming mouse for desktop/laptop computers designed by Logitech; this is a laser mouse with a couple of special features that are specially made for people who play games.
The g5 looks very similar to his twin the g7, the g7 was a wireless mouse with a battery pack that fitted underneath the mouse to power it, the g5 is a wired mouse and instead of a battery pack this mouse have a weight pack where you can fill the small container with little round weights that count up to sixteen weights, eight 4.5g and the other eight is 1.7g that can be added or removed to make the mouse either lighter or heavier according to your likes.
The G5 do not only have the normal left click, right click and mouse wheel but it has additional buttons that are set there for gaming purposes, like say you play a game where you have more than one weapon and believe me when I say that most of the games that consist of violence and weapons have more than one weapon to use and the extra two buttons on the side of the mouse is to be able to switch faster between your weapons when needed.
There are an additional two buttons that are on top of the mouse behind the wheel, these buttons are there to be able to select between three different mouse speeds that you can set up while installing the mouse drivers.
This Is a great mouse it has a DPI of between 400 and 2000 so that you can select you mouse speed exactly like you would like it, I have one of these mouse's myself, loving it al the way and let me tell you it is a very comfortable mouse, not too heavy or too light plus you can add or remove weight from it, if your are on the look for a new mouse this is a great mouse and if mine breaks I would buy exactly the same one without thinking twice.