The Azenis RT615K+ is a further evolution of Falken Tire's championship-winning Extreme Performance Summer tire, the Azenis RT615K. Developed for drivers of muscle cars, sports cars, street rods and performance sedans who want ultimate grip in warm, dry and wet conditions, the Azenis RT615K+ is not intended to be serviced, stored nor driven in near- or below-freezing temperatures, through snow or on ice.Utilizing the proven internal construction and motorsports-inspired asymmetric tread pattern as its predecessor, the Azenis RT615K+ features Falken's latest Extreme Summer Performance-targeted compound. The updated compound is designed to further satisfy the increased performance expectations of competitive drivers through additional dry grip. The Massive Sport Side Shoulder Blocks deliver extreme levels of lateral traction through turns, and the solid center rib effectively puts the power to the ground by providing constant contact with the road. Inboard circumferential grooves and notched tread blocks help evacuate water from the contact patch, improving wet traction and hydroplaning resistance.Internal construction of the Azenis RT615K+ includes a high-tension casing to help increase handling response and high-speed stability. Twin, high-tensile steel belts are reinforced by a spirally-wrapped nylon Joint-less Cap Ply to promote even wear and durability.Extreme Performance Summer tires exposed to temperatures of 20 degrees F (-7 degrees C) or lower must be permitted to gradually return to temperatures of at least 40 degrees F (5 degrees C) for at least 24 hours before they are flexed in any manner, such as by adjusting inflation pressures, mounting them on wheels, or using them to support, roll or drive a vehicle.Note: Flexing of the specialized rubber compounds used in Extreme Performance Summer tires during cold-weather use can result in irreversible compound cracking. While compound cracking is not a warrantable condition because it occurs as the result of improper use or storage, tires exhibiting compound cracking must be replaced.