Various sizes of Fast Traxx, just need a Super Fast Traxx to complete the line-up! Thankfully it's not impossible to find, just expensive :/ The second is part of my XRC collection, it's almost impossible to get stuck since the tracks run the whole width of the vehicle. This is actually from when I was a kid, XRC had some primo stuff but I guess wasn't as popular (or too expensive) and I haven't seen much of their stuff being passed around these days.