The annex is from alpine in ringwood. You have to be very specific when ordering, we have 3 friends with the cubby and they are all different heights, you can also request windows in the cubby as they are not standard and also the door placement. You also need to request zips in the front and back walls as the annex is difficult to put up without them. With our new van we nearly ordered the annex from tebbs but found out the cubby is smaller and cannot be assembled alone. I am trying to convince alpine to make these PVC bed end covers as our friends had someone make them at great expense. They are attached with press studs in replacement of the bed flies.