This is a specific upgrade or replacement part for Tamiya radio-controlled cars. It's the JR HG Multi Roll Setting Stay, also known as a J-Cup, made from 1.5mm thick carbon fiber. The part number is 95131. If you're deep into tuning your Tamiya chassis for better handling, this is the kind of part you look for.
Carbon fiber parts like this are popular in RC racing because they're super lightweight and stiff, which can help improve the car's suspension response and overall handling precision. The \Multi Roll Setting Stay\ suggests it's part of the car's anti-roll bar or stabilizer system, allowing for fine adjustments to how the chassis rolls in corners.
This is definitely a part for experienced builders who know their way around a Tamiya kit and are looking for that performance edge. Make sure your specific Tamiya model (like the 2020 or other compatible chassis) can use this part before you buy. It comes as a single component, ready for you to install in your build.
