I think RD-10 is my favorite RD car out of all the RD cars. RD stands for Racing Drone, just in case you didn't know by the way. They're from Hot Wheels AcceleRacers, something that I definitely watched as a kid. It's also one of my favorite Hot Wheels fantasy casting in general too. I really love the casting's low, fast, and futuristic look. The asymmetrical aspects of the casting is really awesome too. Hot Wheels did a sweet job designing this piece!