The authentic's only come in 4 flavors. 700mAh for the 350's, 1100mAh for the 490's & either 1600mAh or 2000mAh for the 650's. Of the 2 650's, the 1600mAh has a better discharge curve than the 2000mAh variety.
I see that there are some new ones on the market (800, 1200 & a 2200) with a black...