Amazon began allowing consumer packaged goods brands to place sponsored ads in AmazonFresh, its online grocery service that is only available to Prime members for an extra cost.

Products sold through the AmazonFresh program are eligible to participate. Frito-Lay and Nestle Waters, initially spotted by another media outlet, ran ads in search results and the product detail page.

Brands and agencies began receiving the email Thursday morning. “You already know the great benefits of Sponsored Products on Amazon Advertising,” per the email. “Now you can add your ASINs with AmazonFresh offers to new or existing Sponsored Product campaigns.”

The ASIN — Amazon Standard Identification Number, is a 10-digit number that identifies products. 

The ads only will serve up to AmazonFresh customers.

“In the past if you searched for avocados in an area where AmazonFresh is available, whatever came up first, came up first mostly based on things like reviews,” said Trevor George, CEO of Amazon-focused agency Blue Wheel Media. “Now avocados will pop up first based on the advertising.”

The ads will work similar to other Amazon marketplaces using Sponsored Ads, on a keyword cost-per-click basis, George said. “It’s basically the same as Google Ads.”

eMarketer estimated that Amazon’s share of ecommerce food and beverage sales in the U.S. would reach 31.8% in 2018. That same year in May, CNBC reported about 75% of Whole Foods shoppers were Amazon Prime members.

When asked how these highly-targeted ads will prompt consumers to purchase the products, George doesn’t know if they will react differently to an advertised “fresh product,” whether they trust Amazon search results more, or if “conversation rates will follow suit with the marketplace.”