Abstract: A web for a rotary heat exchanger is configured for transfer of thermal energy and/or moisture to and/or from a fluid. The web includes first profiled sections and second profiled sections configured to protrude in opposite directions, each a fluid passage. The first and second profiled sections form a plurality of fluid flow channels, each fluid flow channel having a main fluid flow axis and being configured to allow fluid flow at least partially along the main fluid flow axis. Each fluid flow channel is formed by alternating at least one first profiled section and at least one second profiled section along the main fluid flow axis and by aligning the fluid passages of the alternatingly arranged first profiled section(s) and second profiled section(s). Each fluid flow channel has at least one lateral opening allowing fluid flow to at least partially travel between adjacent fluid flow channels.