Everyone is stuck at home during the pandemic making out-of-home (OOH) ads useless. Yet Burger King has found a way to make them relevant again: by inviting people to use images of the brand’s billboards during their video conferences. In return, Burger King is giving out buy-one-get-one codes for its Whopper sandwich.

To participate, fans need to download one of the billboard images from Burger King’s Twitter account and use it as the background in their video conferences. After they upload a photo on Twitter showing they used one of the backgrounds, tagging Burger King and the hashtag #HomeOfTheBillboards, Burger King will DM them a buy-one-get-one-free code. Fans can redeem the code, valid from April 28 to May 1, on the Burger King app.

Burger King’s integrated activation is a strong example of how brands can repurpose existing creative during the pandemic. In addition to increasing brand visibility, the activation will help Burger King increase its mobile app downloads at a time when apps are competing for consumers’ attention in lockdown.

Coronavirus hit the OOH industry hard: Outfront Media’s stock dropped 64 percent since late February and Clear Channel is down to under a dollar ($.45) for the first time. Before the crisis, revenue for OOH grew seven percent in Q3 2019 to about $2 billion and $6.4 billion year-to-date through the first three quarters of 2019, according to the Out of Home Advertising Association of America.

The #HomeOfTheBillboards offer is part of a larger stay-at-home push launched this week. Burger King released three television commercials that include a scannable quick response (QR) code, which users can scan to redeem a free Whopper with a purchase through the Burger King app. From now until April 30, Burger King is giving away 10,000 Whoppers.

The third push includes Burger King’s 3 for $3 Challenge, which asks customers to post a screenshot of a video call with at least two friends to Twitter and Instagram with the hashtag #BK3forFreeChallenge, for a chance to win one of 50 e-gift cards that cover the cost of its 3 for $3 menu. The promotion ends April 28.