On Weather Shirt Men's The On Clima-Shirt for men is the perfect layering piece for running in chilly weather or for wearing casually during your errands. This super soft top features excellent breathability from micro-ventilation-patterning, keeping moisture under control during activity. Laser-cut ventilation at the back provides further airflow and the adjustable V-neck design allow you to personalize this top according to the climate. Reflective On logo featured at left side hem.Flexible Polyester/Elastane and 4-way-stretch Nylon/Elastane protective fabric with laser-cut ventilation at the back.Features anti-bacterial treatment to maintain freshness.Special Sizing Note: The manufacturer indicates apparel fit as being one size down from size featured on label. Due to this note, we suggest sizing up from your normal size. Sizing Medium: 38-39" chestLarge: 40-41" chestX-Large: 43-44" chestXX-Large: 45-46" chest*Measurements refer to body size, not garment size.