Bisson Custom Mufflers (makers of all types of fine custom mufflers) is marketing excellent-quality hats with it's name on them.
However, these hats are different. Remember the hats worn in the French Foreign Legion? They had curtains on the back, to protect the wearers' necks from the hot sun.
Remembering that amenity, Bisson has a similar hat for modelers, so they can brave the hot sun and not worry about getting their necks burned doing their favourite thing. When not needed, the curtain can be folded up into the hat when it's worn.
It's great sun protection!