Sealing gasket for railway vehicle

A railway vehicle, with an engine or towed, comprising a body and at least one air conditioning unit topping said body in a vertical direction (Z), the body comprising at least one continuous rib situated across from the air conditioning unit in the vertical direction (Z), and the railway vehicle further comprising at least one sealing gasket between said body and said air conditioning unit with its main direction (Z1) parallel to the vertical direction (Z), wherein the sealing gasket comprises a lower gasket part provided with a receiving slot suitable for receiving the rib of the body and an upper gasket part opposite the lower gasket part in a main direction (Y1), and suitable for sealably bearing against the air conditioning unit, the gasket being characterized in that the hardness of the lower gasket part is greater than that of the upper gasket part.