The Fishing Tackle is a quest item used in the Tackle the Day quest, given by the NPC Fisherman located in the Fishing Village monument. It was introduced to RUST in the Missions and QoL update.
Once the quest is accepted, the tackle box must be located, and its contents must be returned to the Fisherman to complete the mission and receive the reward.
The Fishing Tackle serves no additional value outside the Tackle the Day quest chain, as it does not provide a fishing purpose or boost.