The PRO parts kit is a 3 box set loaded with a variety of screws, bolts, stabilizer studs, washers, cam spacers, e-clips, bolt spacers and much more in large assortment of sizes. Its the perfect kit that will supply the lost part you can never seem to find. Each box is equipped with a guide that will tell you the exact size and name of each part that's inside the kit. Kit includes a thread gauge, basic parts kit with 310 pieces, parts kit 2 with 85 pieces and parts kit 3 with 45 pieces for a total of 440 pieces.