A ski mask, also known as a balaclava, is a type of headwear designed to cover the entire head, face, and neck, leaving only the eyes, mouth, and sometimes the nose exposed. It is typically made from warm, stretchy materials like wool or synthetic fabrics, making it ideal for cold weather activities such as skiing, snowboarding, or hiking. Ski masks are popular among outdoor enthusiasts for their ability to provide warmth and protection against wind and cold. They come in various styles and colors, and some feature ventilation holes or openings for added comfort. Many people also wear them for fashion or as part of a costume.