From the Manufacturer:
TAC-DR-05 - Toytec Front Differential Drop Kit.
This kit allows you to lower the front differential reducing the angles on your c.v. axles and boots which can help prolong the life of these components.Our 1" diff drop spacers are machined from high quality 6061 t-6 aluminum, come with grade 8 mounting hardware, and installation instructions.Kit also includes 4 spacers and longer bolts for the OEM skid plate.** Skid plates on TRD Pro editions, special edition models, and aftermarket skid plates may require different skid plate spacer bolts or modifications.