How Harpex Pellets Validated U.S. Market Entry on Amazon

Harpex Pellets is a family-owned manufacturer based in São Paulo, Brazil, specializing in air gun pellets. Before entering the US, the business had already established product demand and advertising experience on Amazon in the Brazilian marketplace.

Recognizing the significantly larger volume opportunity in the US, Harpex expanded internationally with the goal of validating demand and building a scalable foundation for long-term growth.

The Challenge

Harpex Pellets entered Amazon US as a new advertiser, but not as a new Amazon seller. While the brand had experience selling and advertising in Brazil, the US marketplace introduced a higher level of competition and required a more deliberate approach to campaign structure and scale.

At launch, the US account relied primarily on Sponsored Products automatic campaigns with limited daily spend. There was no manual campaign structure in place to intentionally build keyword relevance, improve rankings, or guide growth.

To justify continued cross-border expansion and increased shipment volume into the US, Harpex needed to prove that advertising could drive meaningful sales growth—and that ACOS would improve as investment increased.

Why Quartile

Harpex needed a partner that could support a new-market launch with clarity and discipline. The team was still developing its understanding of Amazon Advertising and required a proven framework and expertise to move from early traction to scalable growth.

Quartile was selected to provide structure, automation, and ongoing optimization—allowing Harpex to increase investment with confidence while maintaining control over ACOS during the launch phase. Every Quartile client also receives a dedicated Customer Strategy Manager, providing the expertise they were looking for in their day-to-day operations.  

The Solution

Quartile began with a full account review to understand which products were already active in the US marketplace and how the existing automatic campaigns were performing. Early data from those campaigns was used to identify promising search terms and determine which products should receive the highest advertising focus.

From there, Quartile built a Sponsored Products structure that combined automatic and manual campaigns. High-performing targets identified through the automatic campaigns were converted into manual campaigns, supporting faster keyword relevance, stronger rankings, and increased sales volume.

The account followed Quartile’s standard launch framework to ensure campaigns were live, monitored, and continuously optimized. As performance improved, Quartile’s automation supported ongoing discovery and expansion while maintaining control over ACOS.

Results & Impact

Following launch, Harpex Pellets established strong traction in the US marketplace.

• Average daily sales increased by 540%, confirming product-market fit

• ACOS improved by 40%, demonstrating that advertising became more cost-effective as sales grew

The performance validated the US expansion and gave Harpex the confidence to increase inventory investment, plan additional production capacity, and commit to continued growth in the market.

Future State

Harpex Pellets now operates with a structured Amazon Advertising foundation in the US. Campaigns are designed to support continued growth, and the business has greater clarity on how advertising contributes to sales momentum and market expansion.

Quartile continues to support optimization and opportunity discovery as Harpex evaluates higher investment levels and potential expansion into additional Amazon marketplaces.