These two servo kits will enhance the shift quality and extend durability of any 700R4/4L60E/4L65E transmission. Since the servo applies the 2-4 band in 2nd gear, releases it in 3rd and reapplies it in 4th, the servo plays a vital role in the operation of your transmission. Easy-to-install with the transmission in the vehicle. Kits may be used individually or combined to create the ultimate servo for your 700R4/4L60E/4L65E transmission.