The Ecsta PS91 is Kumho's Max Performance Summer tire developed for the drivers of performance sedans, sports cars and sport coupes who want a tire with performance that matches the capabilities of their top-level automobiles. High-speed performance and handling in the dry and wet are emphasized, and like all summer tires, the Ecsta PS91 is not intended to be driven in near-freezing temperatures, through snow or on ice.Formula 3 racing tire technology trickles down to the mainstream in the Ecsta PS91 with a new Carbon Black and Silica compound utilizing Max Grip Performance Resin to create maximum performance potential. Handling, responsiveness and high-speed stability are emphasized through enhanced block stiffness created by the C-Cut 3D design and the notched, continuous center rib. The 3D Dimple Design heat dimples minimize thermal buildup in the tread blocks, improving durability during hard use. Four wide, circumferential grooves evacuate water from beneath the contact patch, increasing hydroplaning resistance and wet handling.The internal construction consists of a strong, two-ply rayon cord casing supporting two wide, high-tensile strength steel belts. High-speed capability is further bolstered with two full-width nylon reinforcement cap plies for improved handling responsiveness, stability and durability.