The Colt CALM S18‑300 is a high‑performance acoustic louvre designed for environments needing both ventilation and noise control. Its 300 mm straight blade profile provides enhanced sound reduction, achieving Rw (C, Ctr) 22 (‑1, ‑5) as tested to BS EN ISO 10140‑2:2021, while maintaining excellent aerodynamic efficiency (Cv 0.161). With a modular design, robust steel construction, and optional finishes, it ensures flexibility, durability, and long service life.