This is a "Billet Aluminum Super Servo Kit" for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6 200R4 Transmission. This servo will apply up to 17% more holding pressure due to its greater apply area. It is a longer lasting, more adjustable, stronger material, with top grade sealing properties compared to stock.
