Fabric: Thermal knit tops are typically crafted from a specialized knit fabric that is designed to trap body heat, providing insulation against cold temperatures. The fabric composition often includes materials like cotton, polyester, or a blend of these fibers. Some thermal tops might also incorporate spandex for added stretch and flexibility.

Waffle Knit Texture: One distinguishing feature of thermal tops is their waffle-knit texture. This unique texture not only adds visual interest but also creates air pockets in the fabric, enhancing its insulation properties. The raised, textured pattern helps retain warmth while remaining breathable, preventing overheating.

Long Sleeves: Thermal tops commonly feature long sleeves, ensuring coverage and warmth for the arms. The sleeves typically have a snug fit, which helps in retaining heat close to the body.