A fluid line element for building a fluid line section comprising a plurality of identical fluid line elements, wherein the fluid line element comprises: —an element body, —a first throughflow opening provided on the element body and a second throughflow opening, different from the first, —and a flow channel provided in the element body, which fluidically connects the first and the second throughflow openings for throughflow along a channel path. In a first region of the fluid line element, located closer to the first than to the second throughflow opening, a throughflow body formed separately from the element body is provided, which —forms a part of the flow channel, —is formed from a material having a lower elasticity modulus than the material of the element body, and —on the longitudinal end thereof facing into the interior of the element body, comprises a valve seat formation surrounding the channel path.