The Type segmentation of the Horizontal Flow Wall Modules market distinguishes four principal configurations: modular panels, custom‑engineered units, prefabricated assemblies, and retrofit kits. Modular panels are produced in standardized dimensions, enabling rapid deployment and economies of scale; they account for roughly 45% of total market revenue due to their broad applicability across municipal projects. Custom‑engineered units are tailored to site‑specific hydraulic and chemical conditions, driving higher unit prices and representing about 25% of the market, particularly in high‑value industrial settings. Prefabricated assemblies combine factory‑controlled quality with site‑level integration, contributing an estimated 20% share as developers prioritize reduced construction timelines. Retrofit kits, designed to upgrade legacy treatment structures, occupy the remaining 10%, reflecting niche demand from utilities seeking cost‑effective performance enhancements. Collectively, these type categories shape the market’s cost structure, technology diffusion, and competitive dynamics, providing a clear framework for forecasting growth trajectories across different customer segments.