Abstract: The present invention provides a modular device and kit utilizing a plurality of individual components which form an easily collapsible and transportable leg support used to support the leg, foot, and/or ankle in a fixed position. Accordingly, when the components are arranged together, the assembled configuration forms a three-dimensional leg support device. In the unassembled position, the individual components are designed to maintain a generally planar shape so that each of the pieces that form the assembled unit can lay flat against each other. In this configuration, the collapsible leg support device can be easily stored, shipped, or moved from place to place.