HBO made good on its promise, throwing the doors open on a free streaming buffet of some 500 hours of premium content Friday morning.

The free #StayHomeBoxOffice programming — served up without any ads — includes every episode of nine HBO series: “The Sopranos,” “Veep,” “Succession,” “Six Feet Under,” “The Wire,” “Ballers,” “Barry,” “Silicon Valley” and “True Blood.” Also available to watch without an HBO subscription are 20 movies from corporate sibling Warner Bros. and 10 HBO documentaries and docuseries.

As of Friday, April 3, at 8:30 a.m. ET the mobile apps and websites for both standalone streaming service HBO Now (hbonow.com) and HBO Go (hbogo.com) for pay-TV subscribers each display a new row that says, “Stream for Free: No Subscription Required.” Meanwhile, the HBO Now app on Roku did not allow unauthenticated playback of the titles.

Unfortunately for those outside the United States, the basket of free-to-stream HBO content is available only in the U.S. HBO has not said how long it will offer the free content except that it will be for a “limited time.”

In announcing the promo, HBO invoked the current coronavirus pandemic, saying it was opening the content vault “to provide some entertainment relief for those doing their part to keep everyone safe and healthy in this time of social isolation.”

But more than anything, the premium cabler’s move is designed to whet TV fans’ appetites for its content and persuade them to join as paying subscribers. The free promotion is HBO’s biggest execution of the industry’s long-standing “sampling” strategy, which typically involves making an episode or two available for no charge. Friday’s launch comes at least a month ahead of the scheduled May debut of HBO Max, which is effectively a superset of what’s currently on HBO for the same $14.99 monthly price.

HBO isn’t giving away everything for free, of course. Several of its most popular shows remain behind the paywall, including “Game of Thrones,” “Westworld,” “Big Little Lies,” “Euphoria” and “Chernobyl.” WarnerMedia cited each of those series as having seen big audience increases during the COVID-19 lockdown. The media conglomerate said overall streaming of HBO Now increased more than 40% from March 14-24 compared with the previous four-week average.

In addition to being available via HBO Now and HBO Go, the nearly 500 hours of free programming also will be coming to the platforms of participating U.S. distribution providers within the next several days, HBO said.

The full list of free titles available to stream on HBO can be found here.