Like I said, these replace the existing balloon KN5s in the sx Le Mans track. You'll need to find that track at GTP if you haven't got it already. It's an FM7 rip, so you WILL burn in hell for all eternity, but it'll be worth it. You'll need to rename the KN5 to suit the config on other tracks, or create a config if the track doesn't have one for balloons. But as these balloons have really been made for ONE SPECIFIC TRACK then a lot of what I just wrote is just a waste of my fingerprints. Have fun, ask at GTP if you get lost. Is that all worth an extra star now..? ;)