Latest from bones wheels the barte signature stf wheelstreet tech formula stf is specifically engineered from top quality components to obtain all the best properties necessary for the ultimate in street wheel preformancebones wheels have created a wheel with substantially higher rebound for more speed and amazing slide capabilities while maintaining a resistance to flat spotting well beyond any standard wheelspecificationsdiameter 52mmwidth 31mmhardness 83bformula stfshape v1