Odell Beckham Jr. models looks from 13 x twenty, his capsule collection for Bloomingdales.

Sports sells.

That’s the lesson Bloomingdale’s has learned over the past several years as its collaborations with professional athletes and leagues have caught the attention of its customers.

So for this fall, the retailer is partnering with New York Giants wide receiver Odell Beckham Jr. on a sportswear line that will launch in September.

The line, 13 x twenty, is being produced by knitwear brand Twenty Tees, a collection created by David Helwani. Beckham’s jersey number is 13.

Kevin Harter, vice president for fashion director at Bloomingdale’s, put the two together to create the line, which will be exclusive to the retailer. “David has his own line and he’s also done a lot of great product for Public School and Drake’s collection, so we thought he would be a really good partner and would get Odell’s aesthetic.”

Harter admitted that Beckham was originally “on the fence” about creating his own collection “but we really wanted him and waited for him to say yes.” He and Helwani visited Beckham’s home in New Jersey with samples and with the athlete’s blessing, 13 x twenty was born.

The collection of ath-leisurewear includes knitwear basics that range from sweatpants and hoodies to T-shirts and jackets. Prices range from $85 for tees to $595 for a wool varsity club jacket.

The products will be available at the select Bloomingdale’s stores including the 59th Street flagship, North Michigan Avenue unit in Chicago, the Beverly Center in Los Angeles and others, as well as on the retailer’s web site at the beginning of September. Beckham will also be featured on the cover of Bloomingdale’s Best of Men’s catalog, where he will discuss fall fashion and the inspiration behind the 13 x twenty collection.

“I’ve wanted to step out with my own collection for a while now but had been searching for the right time and opportunity,” Beckham said. “Bloomingdale’s introduced me to David Helwani, the founder and creative director of Twenty Tees. We immediately hit it off and went from there.”

Harter said he expects the collection will be quite popular, especially in New York. He said this initiative is part of the 100 percent Bloomingdale’s program, which is championed by chief executive officer Tony Spring, who encourages the merchants to come up with different concepts and collections only available at the store.