These Aluminum Threaded Shock Bodies are genuine HPI option parts for Cup Racer cars. They're aluminum shock bodies that replace the stock plastic parts for increased strength and they're gunmetal anodized for custom looks. These shock bodies are threaded, making ride height adjustment quick and easy. These are genuine HPI option parts, precision machined to exact HPI specifications for a perfect fit. Each package contains 2 aluminum threaded shock bodies and 4 stop rings.