Hyper Kewl Cooling Vest Blue by Techniche Size Small fits a 33" to 36" chest, according to the website Stay cool on those long summer rides. Helps combat heat stress. Lightweight, durable, reusable, and washable. Many more applications for hot outdoor activities like construction work, sporting events, fishing, boating, and extreme sports. Evaporative cooling system helps keep you cool even through the hottest summer ride Only requires two minutes of soaking in water to activate Polymer embedded fabric holds the water and keeps you cool as the water evaporates Outperforms the competition by having and increased evaporative surface area, keeping you cooler Remains hydrated for several hours