SevenStuds Hi, this is for a set of 4 adapters. If you're in doubt with other products a good way to find out is to also see the interactive 3D preview. It directly views the model that is printed. Enjoy!
SevenStuds@hoklywood: I didn't find the the exact model again, but here is a similar wheel with the same dimensions:
Hi Casper, the file contains one wheel. You can generally see the contents of what is printed from the digital previews and interactive previews.
To compare, a 43mm wheel is on average 11€ and a 56mm wheel is about double that. The pricing is very much influenced by the bounding box volume of the model.