ThermHex polypropylene honeycomb cores with thermoplastic top layers are already used in the automotive industry. The material we use for the boot floor of the Maserati Ghibli and the Jaguar F-Type is, for example, produced by Renolit under the name Gorcell. In Japan, the technology of Gifu Plastics is marketed under the name Teccell and is used, for example, for the trunk cover of the Toyota Prius PHV. In these applications, a cost-efficient weight reduction combined with good recyclability was successfully obtained (Fig. 1).