A tongue with edge sections that are used to glue the tongue into a groove of panel. A tongue for connection of a building panel, said tongue is of an elongated shape and made of molded plastic, the tongue including at least two protrusions at a first long edge of the tongue, wherein the protrusions are bendable in a plane parallel to the upper surface of the tongue and extending essentially in the parallel plane and, wherein the tongue has a second long edge, which is essentially straight over substantially the whole length of the tongue and the tongue includes a gluing part configured to be glued into a groove at an edge of the building panel.