This EPD covers a product group comprising GF INSTAFLEX polybutene (PB) pipes in dimensions ranging from 16 mm to 315 mm, manufactured at 2 production sites in Germany and the Netherlands. The products included in this EPD are designed for the installation of drinking water distribution systems in residential, commercial, and industrial buildings. The covered product portfolio includes pipes with varying diameters, wall thicknesses, pressure classes, and application requirements. While the specific technical performance characteristics differ depending on product type and dimension, all products fulfil the same primary function of transporting potable water within building installations. The environmental results declared in this EPD represent averaged data for the included product and factory group. The declared values are based on production-weighted average datasets representing the manufacturing sites and product variants included within the scope. Product-specific environmental impacts may vary depending on dimensions, material consumption, and manufacturing location. The reported impacts therefore represent the average environmental performance of the covered product portfolio rather than a specific individual product.