Adventurer's Fishing Rod Part
The adventurers fishing rod pieces are obtainable after receiving the quest to get the adventurers fishing pole has been received from the adventurer.
Once the quest is received the adventurers fishing rod pieces have a high chance of dropping off of zombies. The pieces are used to craft the adventurers fishing rod which can be crafted in a work bench.
You cannot pick up a fishing rod part if you already have a fishing rod part of the same type in your inventory. However if you have multiple of the same piece you can hold them in your inventory as long as you are collecting each items from chests.
Attempting to use the crafted fishing rod causes it to break, and you will not receive any rewards from the adventurer.