This does NOT come with the rotating base, the ATMega Arduino board or the "SainSmart Control Palletizing Robot Arm Shield" without these parts the arm is just a pile of useless parts.
SainSmart customer support is a joke. They are based in Hong Kong and if you try to order the parts from them they will lose your order and get it wrong and not respond to emails. A month later I still don't have the shield. I will never, ever, purchase anything from SainSmart again!!!