Nfera Su4 Ultra High Performance Summer. The NFERA SU4 by Nexen is a summer high performance tire that will deliver when you need it most–on wet surfaces, when braking and negotiating corners at high speeds, it will not let you down. Increased block stiffness and pressure distribution keeps tires firmly in contact with the road. Specifically designed wide and asymmetric grooves channel water away for best-fit driving performance in the rain. The NFERA SU4 also includes a high stiffness rib for precision handling at high speeds. A great affordable alternative to more expensive high performance tires out there. *By request/order.