Twitter Inc. is giving retailers and other brands a new way to goad consumers into tweeting about their businesses.

Twitter today rolled out a tool called Instant Unlock Card that aims to compel  consumers to tweet in order to access exclusive content from a  merchant. Such content might be an exclusive Q&A or product images that become accessible after a consumer sends the tweet. The tool builds on Twitter’s conversational ads launched in January; those ads include call-to-action buttons with customizable hashtags that encourage consumers to interact with the tweet.

In testing, advertisers received an average of 34 earned impressions for every 100 paid impressions, or to put it another way, a 34% earned media rate. The Coca-Cola Co. is among the brands that tested the new tool. The soft drink company’s #TasteTheFeeling campaign aimed to boost engagement with teens by running a conversational video ad featuring influencers with an auto-response to distribute @CocaCola’s branded GIFs in the teens’ feeds. The campaign produced 180,000 mentions of @CocaCola and the branded terms on the day of launch. That helped drive the hashtag #TasteTheFeeling to be a top organic global trend on launch day.

Brands using Unlock Cards can access analytics that let them track engagement metrics, including how many consumers are tweeting with a campaign hashtag and how many impressions the campaign earned. U.S. advertisers also can examine whether their conversational ads are having an impact on their TrueVoice score, which is a metric that aims to track share of brand conversation in real time.

Unlock Cards are available to all advertisers in all markets that work with Twitter’s account teams.