Abstract: A pack of heat transfer plates for regenerative heat exchangers is operationally adapted to absorb heat from a flue gas flowing in one axial direction along the main flow axis and release such heat to a combustion air flowing in another axial direction. The pack includes first and second mutually identical profiled plates which are arranged in mutually contiguous, contacting relationship with double ridges of the first plate intersecting double ridges of the second plate. The double ridges of the first and second plates extending symmetrically and obliquely in mutually opposite directions relative to the main flow axis of the heat exchange media flowing through the pack. The pack includes a third plate having provided thereon continuous extending parallel channel formers. One side of the third plate is in contiguous relationship with the second plate.