Arms eliminate upper ball joint w/ super strong 1in ID Stainless American Uniball. Additional caster is built into Arms for greater align ability to help with problematic leveling kit alignments. Allows for increased wheel travel when used with Dirt Logic 2.5 Coilover shocks. Chromoly tubing reduces flex found in stock arms for more positive road feel. 4340 Heat treated Uniball pin fits into factory ball joint taper without modification to the spindle for easy return to stock feature. Arms are direct replacements for factory arms on suspensions that require additional strength and align ability. Built with same materials as found on Trophy Trucks. .120in Wall 4130 Chromoly Tubing. 1.250in OD. .250in wall DOM Bushing Barrels. 1in ID Stainless Steel American Uniball. 17-4 Stainless Misalignments