Light as always. Stronger than ever. We introduced our first fabricated knuckle over a decade ago. Today, the Pro Series Knuckle takes professional rock racers to an all new level. Tig welded, heat treated 4130 Chromoly Steel legs, and a fully integrated double shear high steer arm makes our latest generation Pro Series Knuckle our best yet. All while holding the same compact & lightweight design philosophy you have come to expect. Please note photos shown here are of our “mid” steer arm setup. Please refer to the drawing below for arm location details. This Pro Series Knuckle is designed for Ultimate Unit Bearings, to install on a Spider 9 Housings w/ 3½” (88.9mm) OD tubes. As shown, a fully pre-welded double shear high steer arm is included. Overview CNC & Heat Treat All components are CNC manufactured out of domestic grade 4130 chromoly steel, legs are now heat treated, and all inner knuckles are machined post-welding for a perfect spherical bearing fit. Every single part is made in the USA, no exceptions, no compromises. ?” Bolts & Bearings The spherical bearing assembly consists of a 4340 Spider Shoulder Bolt, shim washer, spherical bearing, shoulder washer, & type C nut. Combined, each knuckle can withstand over 21,500 lbs (9752.236 kg) of axial loading & over 130,000 lbs (58967.0081 kg) of radial loading. No grease, no weak links, no hassle. 50° of Steering An OEM style 60 knuckle can turn only 38°. Our Pro Series Knuckle can turn all the way to 50°, tighter than any steering knuckle on the market. Our unique fully integrated 4130 double shear high steer arms are perfectly integrated into the knuckle as well. Stronger steering, stronger knuckle. Gussets & TIG Upper outer knuckle gussets add critical strength for steering while lower inner knuckle gussets add extra strength for those high sailing jumps. TIG weld the entire knuckle with high strength high elongation filler rod and you end up with a product fit for the worlds toughest races.