US Patent 8002241 Half block for multi-level interlocking blocks

The present invention is a unitary piece block formed of polymers (such as polystyrene or other high strength polymer) by a single injection molding step which are assembled into a recreational vehicle leveler. The invention ramp provides four sets of four connectors at a top of a floor plate, which are adapted to interlock in cavity structures formed within a cavity on the underside of the block. Two adjacent blocks are secured together by applying to their top surfaces the securing cavity structure of an underside of a third such block. Such blocks can be stacked in an interlocking manner to reduce storage space.