Tony wanted to buy a pair of​ binoculars, but not just any brand. He wanted to buy a pair of Steiner​ Nighthunters, just like the pair he had learned about in his newest copy of ​Peter's Hunt Magazine. He had to visit five different sporting goods stores before he found this brand. For​ Tony, the Steiner Nighthunter is an example of​ a(n) ________.