In motorcycle protective armor standards (such as EN 1621 / GB standards), what is the difference between Level 1 and Level 2 impact limb and back protectors?

1. Level 1 protectors are certified for speeds over 200 km/h while Level 2 is only for parking lot maneuvers
2. Level 2 protectors are made of unpadded rigid metal while Level 1 uses soft inflatable air cushions
3. Level 2 protectors transmit significantly less peak force to the body (higher impact energy absorption) than Level 1 protectors
4. Level 1 protectors can be used for five crashes while Level 2 must be replaced after rain exposure