Its an Optimus from transformers Armada series. The size is ultra (a little bit bigger than a leader class). The robot it self only voyager class size, but what makes it bigger is because its armada (trailer).
I bought it from ebay in about 40USD in a very good condition with a complete accessories.
There's a yellow small car as a minibot also.
There's a small red light in the armada, near the optimus feet.
and this is if with the trailer
It has a great altmod shape, but too bad in my opinion while change into
a robot mode its kind a lack of articulation. The form is very stiff,
well .. means we could not make it with a lot of pose , both of the
robot it self so does the robot and the armada.