Orange County, Calif., is the home to scores of action-sports brands that made their fortunes selling T-shirts, but 7Diamonds cut a different path from its neighbors.

The 18-year-old company decided its mission would be to focus on making men’s woven shirts that sold at places such as Nordstrom and Amazon.com.

But in the past few years, 7Diamonds has been expanding its categories to include blazers, outerwear, shorts and chinos. In February, at the Project trade show in Las Vegas, it unveiled its first T-shirt line, which is a collection of crew-neck tees and pocket tees.

“It’s something we always wanted to do,” said Jocelyn Khalil, 7Diamonds’ vice president. “Button-up shirts are a staple. We’re expanding into a man’s everyday wardrobe. Every man needs a T-shirt.”

The Supima cotton tees come in 10 colors, including white, black, navy, gray, off-white, sea foam, olive green, indigo and a light blue. There are no logos or branding on the tees, which retail for $39. It’s a price Khalil calls affordable luxury.

7Diamonds’ pocket tees put details on the pockets such as embroidery or contrast pockets with different fabrics. They’re a little more expensive, retailing for $49.

T-shirts from prominent European fashion houses can start at $500 and go north of $1,000. Los Angeles–headquartered James Perse crew necks can retail for $60. At the low end, Fruit of the Loom T-shirts sold at Walmart’s e-commerce site (www.walmart.com) can retail for under $5.

Khalil hopes the T-shirts find their way into every man’s closet. “When a guy needs a nice, premium T-shirt, he can get them from 7Diamonds. They’ll say, ‘They won’t let us down,’” she said.

Currently, the tees are selling at www.7diamonds.com.