On each of the fixtures a label with product number, product name and serial number should be found. This is the unique identity each ARRI fixture gets. This product and serial number should be able to be tracked in previous purchasing documents.
Another easy way to distinguish a counterfeit unit is to try updating the fixture with the latest firmware. That will facilitate the fixture with the latest features and easily find out if it is a counterfeit unit. Counterfeit units cannot be...