Pith helmet

A Pith helmet is a type of hat, typically beige, with green cloth if it's intimating Daring Do.

History
Although not exclusively so, Pith helmets popularity seems to be directly tied to the adventures of A.K. Yearling, with many cosplayers wearing the helmets to look like their favorite adventurer. As such, A.K. herself has worn her own Pith helmet throughout her many adventures. Other wearers of the helmet included the Marooned tourist, a group of explorers in their own right who got kidnapped by the Pygolians in the Pygolian jungles.

Design
Pith helmets have a circular baseline with an indented top.