Mainly the United States has made significant movement to take rock crawling mainstream. Crawling course are set up on a rocky mountain face and the objective is for your vehicle to clear a section of the course. The Rock Force 2.2 was designed from the ground up to give you the best competition level base kit. This kit will break the standard rock crawler mold, with the first crawler in the industry using worm gear technology. Worm gear gives you the benefit of a lower gear ration and a smaller diff case area, which comes in handy when maneuvering over a difficult course that calls out for ground clearance.