Affiche Aérodynamique de Casque de Vélo

Professional cycling helmet promotional poster in a vertical composition. A structurally realistic road cycling helmet is suspended in the center at a two-thirds side angle, featuring a [matte ivory white] shell with internal EPS buffer layer and black straps visible only through the vents. The scene features an 'Airflow Cross-Section Doors' concept: three evenly spaced thin rectangular light gray metal door frames stand in front of the helmet, and two narrower door frames stand behind, with ultra-thin fluorescent orange rims on their cross-sections. Four semi-transparent cobalt blue volumetric airflow bands enter from the left, passing through the front frames and helmet vents without penetrating solid shell sections, splitting through inner channels, and recombining into two smooth wakes at the rear. The airflow bands are tangible physical volumes rather than neon light lines. Clean cold-gray studio setting with soft ground shadows cast by helmet, frames, and airflow. Typography: the title '[AERO]' is set vertically on the far right with wide letter spacing, allowing wake streams to pass through the letter negative space; '[VENT 18 / ROAD HELMET]' is printed neatly in the bottom left corner. High-speed studio product photography merged with clean engineering visualization aesthetics. Fully opaque rectangular background, no riders, no bikes, no exploded views, no HUD graphics, no brand logos.