1、Working Principle: Through the waist large wind high speed fan to make a large amount of air outside the body along the body surfaces parallel flows so as to quickly evaporate sweat, reduce the body surfaces temperature. 2、Heat Dissipation: Brushless DC motor, strong wind, running up to 4500rpm, heat dissipation does not get hot, longer service life. 3、Strong Wind Power: Air conditioned clothes using oblique cutting air blade wind technology, strong wind power, small volume, large air volume. 4、Three Wind Speed: Special wind design at the back of the clothes, the wind can blow to the head, three wind speed, can meet your different needs. 5、Breathable Mesh: Cool vest is designed with breathable mesh to prevent the fan from blowing directly on the body, and the fan uses a combination of rotating threads for easy installation. Item Type: Cooling Vest Material: Nylon Number of Levels: Three Levels, One Comfortable Wind, Two Cool Wind, Three Strong Wind (Shipped Without Power Bank) Applicable Scenes: Indoor Environment, Outdoor Environment, Construction Workers, Outdoor Adventure, Etc. Size: Approx. M: Length 66cm / 25.98in, Half Bust 57cm / 22.44in, Shoulder Width 47.5cm / 18.7in, Suitable Height 155-165cm / 61.02-64.96in, Suitable Weight 47.5-57.5kg / 104.7-126.8lb L: Length 68cm / 26.77in, Half Bust 60cm / 23.62in, Shoulder Width 49cm / 19.29in, Suitable Height 160-175cm / 62.99-68.9in, Suitable Weight 57.5-7.5kg / 126.8-148.8lb XL: Length 70cm / 27.56in, Half Bust 62.5cm / 24.61in, Shoulder Width 51cm / 20.08in, Suitable Height 165-180cm / 64.96-70.87in, Suitable Weight 67.5-77.5kg / 148.8-170.9lb XXL: Length 72cm / 28.35in, Half Bust 65cm / 25.59in, Shoulder Width 52.5cm / 20.67in, Suitable Height 170-185cm / 66.93-72.83in, Suitable Weight 77.5-85kg / 170.9-187.4lb Fan Color: Black Vest Color: Light Gray 1 x Cooling Vest 1 x Cable 1 x User Manual