Originally Posted by RockAgainstEmo
They may have some sort of anti-scratch coating, or maybe if it's a thermal the inside is polycarbonate. Any bulletproof lenses are probably just using bulletproofing as a selling point. Overall, I don't think bulletproof paintball lenses will ever come in handy in any real world situation. If someone's shooting at you with a real firearm, having bulletproof lenses on your paintball mask is probably not going to save your life.
It is to demonstrate the amount of force it can withstand, it's like a company designing building structures saying they can withstand F5 conditions. Most likely it will never happen that it encounters that.