More about Roto-Joint Technology….. UMI's Roto-Joint, short for Rotational Joint, allows 28 degrees of total rotation and unrestricted movement throughout the vehicles suspension. The Roto-Joint is designed to work like a spherical rod end while maintaining streetable qualities of a softer bushing. The Roto-Joint is designed to articulate and prevent suspension bind, and since the installed delrin race does not deflect like softer bushings, there is an improvement in traction and a significant reduction in wheel hop. The construction of the Roto-Joint features a 4140 chromoly, hard chrome plated spherical ball which rotates in a delrin race. The 4140 chromoly material and hard chrome plating are designed for extensive wear resistance against hard driving and accumulated miles. The spherical ball rotates in the CNC machined delrin bushing, which is contoured for the spherical ball to allow unrestricted movement as the ball rotates. Delrin is the bushing material of choice due to its high resistance against wear, great tensile strength, and ability to maintain its physical properties. The housing of the Roto-Joint features 4140 chromoly threads, and a CNC machined bushing holder TIG welded together for the utmost in strength and durability. The UMI Roto-Joint is adjustable and 100% rebuildable. This means as the delrin race wears the adjuster ring can be tightened using the optional spanner wrench to apply tension to the ball. If the delrin race would ever wear completely it can be replaced easily.