LiDeR (Lightweight Deployable Radiator) is a passive deployable radiator system designed for small and cost-efficient spacecraft. Based on graphite foils and hooked metal sheets, it offers high out-of-plane thermal conductivity.  The variety of benefits connected to this basic technology enables a range of interesting applications. One of the key aspects is the high thermal conductivity of the passive material. It makes late integration of additional thermal distributive area, as a thermal doubler, or even a thermal radiative area in the form of a deployable panel, possible. Developed under the ESA-funded “HiDuct” activity, LiDeR offers a simpler, lighter alternative to complex two-phase systems.