The RPM Rear A-Arms (#81502) use a flexible, engineering-grade nylon blend (74% recycled nylon) that absorbs impacts without snapping and adds an outboard shock-mounting hole that lowers ride height while slightly stiffening effective spring leverage.
Using the inner hole preserves factory ride height and suspension travel. Moving the lower shock screw to the outer hole reduces the arm's leverage on the shock—lowering the chassis center of gravity, increasing stability on high-traction surfaces, and giving the rear suspension a slightly firmer feel.