Hollofil is a brand of synthetic fiber often used in insulation and filling materials, particularly in products like bedding, jackets, and outdoor gear. It is designed to mimic the properties of natural down, providing warmth and comfort while being lightweight and hypoallergenic. Hollofil fibers are typically created with a hollow structure, enhancing thermal efficiency and moisture management. The material is also known for its durability and resilience, making it a popular choice in various applications.