in regions and the reinforcing structure serves to prevent the vane body 2 from collapsing under pressure the insert 6 can comprise a coating in the region in which it is or can be in engagement with the opening 5 wherein said coating together with a smooth surface of the inner walls of the opening 5 with or without a coating keeps a frictional value between the outer surfaces of the insert 6 and the inner walls of the opening 5 small though not shown in fig1 it is possible for each of the two end facing sides 3 4 to comprise an opening 5 in each of which an insert 6 is arranged in this case each of the two inserts 6 can be assigned a tensing device 7 8 each wherein the two tensing devices 7 8 can be supported on the reinforcing fin 9 alternatively the two inserts 6 can be biased towards the cover and the base respectively by one tensing device 7 8 which in this case can be supported on the two inserts 6 fig2 shows the insert 6 in a plan view onto the vane 1 the vane body 2 and or wall of the vane body 2 which surrounds the opening 5 and forms a receptacle and guide for the insert 6 is shown the insert 6 can be formed as a solid body or as a hollow profile if it is formed as a hollow body it.