Abstract: The heat transmission roll for a rotary cylindrical heat exchanger comprising layers formed by two superposed strips wound around the core, where the first strip (1) is corrugated transversely to form regular waves with wave crests (3) on the one side of the strip, and wave troughs (4) on the other side of the strip (4), while the second strip (2) is basically flat. Formed on all wave crests (3) of the first strip (1) are bulges (5) featuring slits (6), where one of the slit edges is formed into a tongue (7), while the second strip (2) features separate indentations (8) to accommodate the bulges (5) on the first strip (1), where the depth of the indentation corresponds to the pitch (h) of the bulge.