G Fins feature strips embedded in a machined groove and secured with base tube material to ensure maximum heat transfer at temperatures up to 450°C. Made from aluminum or copper, they are compatible with carbon steel, Cr.-Mo. steel, and stainless steel tubes. L Fins are subjected to controlled deformation to achieve optimal contact pressure, enhancing heat transfer and corrosion protection, with a maximum operating temperature of 150°C. They are constructed from aluminum or copper and used with carbon steel, Cr.-Mo. steel, or stainless steel tubes. Crimped Fins are wrapped under tension around the base tube, forming a crimp at the fin's foot and welded at the strip ends, suitable for temperatures up to 250°C. These fins are made from carbon or stainless steel and copper, and are used with carbon or stainless steel tubes.