North Face sweatpants. Size: 100 Color: Cave Blue There's a sense of wear around the knees, but they're still in good condition and can be worn. The thick fabric was very useful. From the website below: Sweatpants made of flame-retardant material, suitable for camping scenes such as campfires. The material, which incorporates a non-halogen flame retardant into recycled polyester, has the property of melting and carbonizing when exposed to fire, making it difficult for flames to spread. The sweat fabric with a pile lining on the skin side feels good against the skin, is soft, and has excellent absorbency. The waist has a spindle specification and is designed to prevent static electricity.