Solid center rib of trapezoidal shape provides high roadholding ability of the car at any speed rate. Special design of wide longitudinal grooves improves gripping characteristics on dry road.
Arc-shaped grooves, that have different depth along the length, increase the rigidity of lateral rib thereby improving road-holding ability and handling. Shoulder ribs are designed as solid ones to increase rigidity that means to increase grip on dry road including road-holding ability when turning.