Moser's Custom built 9" FORD Center Sections are completly assembled and shipped in a specially designed plastic case. Solid Pinion Shims are used instead of the weaker crush sleeves. All units are assembled with special calibrated "Torque Guns", which means no impact guns that will hammer and flat spot bearings and no guessing on your pinion nut torque setting! Each pinion is specifically torqued to the gear manufactures stated setting.