Amazon shoppers in far-flung U.S. towns are getting their packages faster as the company pushes deeper into rural America.

Boka’s premium, fluoride-free toothpaste is now available at 4,500 Walmart stores. The 11-year-old brand’s trajectory shows the appeal and challenge of transitioning from a luxury, niche player into a mass-retail CPG brand.

Amazon is planning to move Prime Day to June from its usual July slot this year, shaking up the timing of a sales event many brands rely on.