Marlin Heavy Duty Bearing Retainer for R154. This is another awesome product from Marlin Crawler! Fits all R-series transmissions [R150F (V6), R151F (Turbo 4Cyl), R154 (Supra), etc]. Made from top quality tool steel and will long out live the factory original. As the factory unit wears out it fails to properly position the main shaft. This heavy duty unit does a much better Job of holding the shaft in the proper position. Includes set of 4 bolts.