This is what I consider to be the most ventilated head protection with a downhill certification. I have a large for myself and have owned several FF helmets over the years, this is easily the most ventilated, important on warm days. It is also one of the most comfortable I have had.
This is a nearly new, size small, 2nd gen Parachute, hard to find in the states. Perfect for BMX also. Size small. Was $340 new.