The phrase "genuine article" means something that is authentic, real, and true. It refers to a person or thing that is exactly what it claims to be, without any imitation or deception. Full definition
Unfortunately, in England, Cayenne pepper is very frequently adulterated, and hence reliance can only be placed on purchasing from respectable wholesale houses, which have a reputation and character for probity and the sale of genuine articles. (fieryfoodscentral.com)
Some background — I met him online, somewhere kinky, and I built him up in my head to be the man of my dreams — husband material, the signed, sealed and delivered genuine article. (30datesblog.com)
Unsurprisingly, that is to the film's benefit, as even the best virtual water isn't going to have the same impact as tanks filling halls and stairways with the unmistakable genuine article. (dvdizzy.com)