About sizes: The following sizes are Asian sizes, which are smaller than UK and European sizes. We recommend you choose 1 or 2 sizes larger than usual. Please check our size chart before purchasing. The size chart is shown in the picture. Optimal heat function: this women's vest with warm inner fleece offers cosy comfort on cold days. The thermal underwear is ideal as a base layer under winter clothing and effectively keeps annoying cold away without being heavy or uncomfortable. Comfortable fit and design: with a subtle slim fit and elastic stretch material, the long-sleeved shirt fits like a second skin. The classic crew neck remains invisible under outerwear, while the seamless finish prevents pressure points. Versatile everyday suitability: Whether as an undershirt under business clothing, as a warming layer for leisure activities or as a comfortable house top, this thermal undershirt adapts flexibly to your daily requirements. Ideal for indoor and outdoor use. Practical use: the smooth surface and soft material make the undershirt the perfect base layer under tight clothing. It ensures a smooth fit without annoying seams and always remains discreetly hidden under your outerwear. Seasonal companion: Specially designed for autumn and winter, this functional underwear supports your heat regulation in changing temperatures. The breathable properties ensure a pleasant body climate in heated rooms and in the cold.