Corvette Style 2-4 Servo Upgrade Kit With O-Rings & Seals. Corrects Soft 1-2 And 2-3 Shifts. Adds Holding Force For Increased Torque Capacity In 2nd Gear. This servo kit alters the 3-4 clutch accumulation rate making the 2-3 shift firmer. Ideal for high-performance applications and is fully compatible with valve body kits. This Improved design is a must for performance vehicles. Does not Require transmission removal for proper installation.