The “L-footed fin” is a circular fin wrapped under tension around the base tube. The feet of the fins cover the whole surface between fins. The L-foot provides a large contact area ensuring a good path for heat transfer from base.

The “Overlapped L-footed Fin” is fabricated with a relatively greater amount of fin material in the foot, ensuring full coverage of the base tube and prohibiting any contact of the ambient with the base tube.

The “Knurled L-footed Fin” is similar to L-footed fin, unless with greater design temperature. The foot of the fin is knurled simultaneously with inner tube, ensuring a
tight contact between the fins and the inner tube.