No one cares what it measures horizontally, because clearance of the axle doesn't happen horizontally, it happened from where the tire compresses under the weight of the Jeep. My 33 inch KO2's measure about 31.5 inches. If what SCiotola said is true, than I would buy KO2's labeled as 37's and treat them as 35's if I wanted 35 inch tires. Also, if you go onto GrimmJeeper and punch in 35 inch tires, its not going to account for the fact that your tire may run small or that it gets compressed by the vehicle. So if you want dead on accurate results for choosing your gearing, go off the exact vertical measurement of the tires at whatever PSI you run them on the road.