You may see some players with a special helmet that you cannot purchase or unlock in the Shop. These were given out during the 2017 Mad Skills Motocross 2 World Championship Qualifier event. Only the top 1000 players during this event earned this special helmet seen below.
This helmet is no longer available to earn and it cannot be bought.
There were also 3 special edition helmets given out to the top 3 players during the MSM2 World Championship Final.
These were awarded to:
1. Bragstad - gold helmet
2. Master52 - silver helmet
3. Djauzzi - bronze helmet