It can be quite tricky to tell which model Bugaboo you have. One sure fire way of finding out, is to look at the pattern of the rubber tread. Some wheels are air and foam filled.
Please see the examples below for guidance:

Bugaboo Rear Wheel – Cameleon1 & Gecko… Air Filled. These can be found on the cameleon1 and Gecko, notice how the tread is now grooved into the rubber in a sort or triangle shape.