Pro Line 10171 03 Class 0 BFGoodrich Krawler T A KX 1.9" Rock Crawler Tires (2) (3.85" OD) Monster Truck which means the geometry stays which means the geometry stays where you set it under cornering load instead of flexing Function knob The Krawler T A® KX (KX is for Key feature: eXtreme traction) is BFGoodrich's Off Road Maximum Traction tire for off road enthusiasts who participate in the extreme sport of rock crawling to challenge their crawling skills and the performance of their vehicles This purpose built rock crawling tire was developed through participation in competition as BFGoodrich® worked directly with full size rock crawling enthusiasts