Sigma SD9 weighs 950 g (2.09 lb / 33.51 oz) and has external dimensions of 152 x 120 x 79 mm (5.98 x 4.72 x 3.11″). Considering that the average weight of DSLR type cameras is 774g, Sigma SD9 is a significantly heavy camera for its class. With a thickness of 79mm, it has an average thickness.
In order to give you a better idea about the real life size of Sigma SD9, we have added an image of how it looks next to a credit card and an AA type battery.
Now lets compare the weight and thickness of Sigma SD9 with its main competitors:
Sigma SD9 doesn't have any environmental sealings on its body so you got to be extra careful to protect it against water and dust. If you shoot under these conditions very often, consider checking Top DSLR Cameras with Weather Sealing page.