When I started I used the bags once I learned about the dangers of the packs. I started racing again at the local track (now shut down unfortunately. Retired, not business related) and they required it. Here at the house, I use nothing. I set them on top of my charging case's acrylic (can be seen in the charging case videos) and let them go. But, I don't start a pack and walk away. I'm usually always right there with it.