The B&M Shift Improver Kit the easiest way to get the stout performance you've always wanted out of your automatic transmission - and you get two modes of performance to select from: Heavy Duty, or Street/Strip. It's our least expensive and simplest to install kit. All you need are a few dollars and some hand tools! In the space of an afternoon, you can turn your transmission into a B&M-tuned unit! Just ask the thousands of satisified customers that have installed one in their transmissions! Stage 1 - Heavy Duty Firm positive shifts without loss of driver comfort for improved performance in all street vehicles. Recommended for regular passenger vehicles. Stage 2 - Street/Strip Provides very positive shifts for high performance street use or for competitive events. This model is for the enthusiast who wants the hardest, quickest possible shift. Application: 1980-1992 AOD