Yes, it is absolutely possible to achieve a slightly firmer cushion density through a dedicated OEM program. Most reputable manufacturers offer flexibility in material specifications as part of their custom development services. The process typically involves selecting from a range of foam core materials—such as high-resilience polyurethane, memory foam, or latex blends—each with different density and firmness profiles. During the prototyping phase, you can request samples with increased density ratings, often measured in pounds per cubic foot (PCF), to fine-tune the final feel. It's crucial to communicate your specific firmness requirements early in the design process, as density adjustments can impact other factors like durability, support, and overall product performance. A reliable OEM partner will guide you through the available options, perform necessary compression tests, and help balance firmness with comfort to meet your exact product vision.