The DK2 is our professional motion solution for home setups with 500lbs or less. It features 2" of travel and uses the same algorithms as the DK2+ and DK6 to accurately represent motion or what we call Motion Integrity™. The DK2+ and DK6 use the larger Technic motors, with more torque and can better represent motion requests with more weight on the chassis or up to 800lbs, and hence are better suited for heavier rigs or for sim racing centers where the final sim rig weight is unknown. The DK6 uses the same motor as the DK2+ but has triple the stroke or travel and is better at representing the natural suspension travel and flight simulation telemetry. More technical details can be found here: DK System Comparison - Sigma Integrale