The Advanced shock is the primary shock for NC cars. The valving numbers on the bottom of the shock provide the valving information of the shock. Example 3/4, this would mean the shock has a 3 Rebound setting and 4 Compression setting. These shocks are sold with the Standard rod end for the bottom of the shaft as pictured. With the 02, Kong, and Grizz model cars we typically use the Extended rod end for the right rear shock. This is sold separately. Please contact the shop via email or by phone for suggested shock set-ups for your car, class, and track. These are typically Drop Shipped seperatly within 2-5 days of order processing.