The angler hat is acquired randomly from completing a game of Fishing Trawler. The hat grants 0.4% bonus Fishing experience. A fishing level of 34 is required to wear it. The Angler hat is 1 of 4 pieces of the Angler’s outfit.
When a player receives it a message in the chat box states The luck of the sea is in today. You spot a piece of fishing gear caught up in the netting!