Abstract: A radiotherapy treatment table top device (1) with high rigidity and load carrying capability, while at the same time providing a low attenuation of radiation, includes a core (2), preferably made of a foamed material, at least partly enclosed by a skin (3,3?) that preferably is made of a fiber material, whereby the core (2) is sandwiched between the skin (3,3?) on opposite sides (6,7) of the table top device (1). The core (2) is non-homogenous with respect to density. Preferably the core has a varying density, with higher density close to at least one interface (8. 8?) with the skin (3), such as a higher density in an upper layer (4) and a lower layer (5) close to the skin (3,3?) and lower density towards the central plane of the core (2).