One of the Dominatrix's more salient features was the ability to adjust its weight, and this is retained with the Eclipse. Slide off the front panel of the device and you'll find a set of four weights underneath, totally 18 grams. You can easily remove some or all of the weights to make the mouse lighter within seconds, although personally I preferred this particular mouse in its fully laden state. Because I'm so manly and strong. Or something.

While the scroll wheel requires no introduction, by default the button below it allows you to quickly and easily change the DPI settings of the mouse, clicking it upwards to increase it or downwards to decrease it. I'm a little torn as to whether this is easier or better than the button system on the Dominatrix, but I think I favour the Eclipse's implementation slightly on this count.