Bush hat

This is a boonie hat (also spelled boony hat).
​Depending on the context, it is also commonly referred to as:
​Tactical Sun Hat / Military Boonie
​Wide-Brim Bucket Hat
​Safari / Outdoor Sun Hat
​Key Features Shown:
​Chin strap (Drawcord with toggle): Secures the hat in windy conditions.
​Branch loops (MOLLE webbing): Webbing band around the crown originally designed for holding camouflage foliage.
​Ventilation eyelets & snap buttons: Keeps the head cool and allows the brim to be pinned up at the sides.