Juul, the e-cigarette company that has become ubiquitous among teens, is launching its first television ad campaign targeting adult smokers as it faces criticism that its fruity flavors are designed for underaged users.

The San Francisco-based e-cigarette company plans to launch over the summer its new TV campaign, featuring testimonials from adults who have used Juul to stop smoking cigarettes, executives said. The ads are likely to draw some controversy. Tobacco companies have long been restricted from most TV or print advertising, with marketing regulations stretching back to the 1970s. Federal and state regulators haven't yet applied the same standards to e-cigarettes, which are a relatively new product.

Juul will initially spend almost $10 million for TV slots airing on national cable channels after 10 p.m. local time. The ads, a series of three different commercials, are aimed at adults 35 years and older, executives said.

The 60-second spots feature three former smokers between the ages of 37 and 54 who talk about their experience with cigarettes, including how smoking strained relationships or isolated them from families and friends, and how Juul helped them quit smoking.

The campaign marks the start of a year Juul will need to spend proving to regulators its product is ending up where its supposed to — in the hands of adult smokers, not teenagers. And fresh with nearly $13 billion in cash from Marlboro-maker Altria, Juul has money to spend to try to change minds that it's not the second coming of Big Tobacco.

"It's clear that we're focused on the mission of the company to convert people off combustible cigarettes," said Ann Hoey, Juul's vice president of marketing. "This is campaign that is a sort of an honest, straight down the middle of the fairway, very clear communication about what we're trying to do as a company."

Juul says its target audience is adults who want to stop smoking cigarettes, but its product has become wildly popular among teens and young adults. Critics have pointed to Juul's first ad campaign, which featured bright colors and youthful looking models, as evidence the company was intentionally marketing to young people. Juul has said it regrets the ads but denies it intentionally targeted teenagers.

The company started overhauling its social media accounts last year to highlight testimonials from adults who had switched. It shut down its accounts in the fall facing a threat from the Food and Drug Administration to fix the "epidemic" of youth e-cigarette use or else have products pulled from the market.

Juul has already captured about 75 percent of the e-cigarette market, according to Nielsen data. However, it's unclear what percent of Juul's sales comes from former adult smokers and what percent comes teens, though critics would say too much comes from the latter group.

In running advertisements highlighting stories of adults who have used Juul to stop smoking, it suggests the company sees an opportunity to reach more adult smokers.

Over the past year, Juul captured 68 percent of the total $3.25 billion e-cigarette market, according to Nielsen data ended Dec. 29 compiled by Wells Fargo's Bonnie Herzog. However, it represented just 3 percent of the $72.81 billion in overall tobacco sales, which includes cigarettes, e-cigarettes, chewing tobacco and cigars, according to Nielsen.

Altria, maker of best-selling cigarette brand Marlboro, announced Dec. 20 that it bought a 35 percent stake in Juul for nearly $13 billion in cash. As part of the deal, Altria will give Juul some of its prime shelf space and add information about Juul to cigarette packs.