Our Chromoly Heim rod-ends are fully heat treated with a radial static load(RSL) rating of 76,200 lbs. The 52100 bearing is heat treated steel and hard chrome plated. The housing has a hard chrome finish. The race is made from a teflon impregnated nylon injection molding.Rod Ends have a 1.25" shaft with 12 threads per inch with a 1" bore. This kit is perfect for fabricating a custom suspension system for your off or on-roading project. Our 4 Link Heim Kit Includes:4 Left-Hand Thread Heim Rod Ends with 1.25" shaft with 12 threads per inch with a 1" bore.4 Right-Hand Thread Heim Rod Ends with 1.25" shaft with 12 threads per inch with a 1" bore.4 Jam Nuts - LEFT-HAND THREAD4 Jam Nuts - RIGHT-HAND THREAD 4 Weld-on Tube Adapters - LEFT-HAND THREAD 4 Weld-on Tube Adapters - RIGHT-HAND THREAD 16 Chromoly Steel, Zinc plated Misalignment Spacers