This is the Fin Gleam Helm. It is light armor, constant nighteye, and can detect life up to 20ft, and breathing underwater. Finding it is not hard, I did it a level 3 with no underwater breathing.
First you must first fast travel to the Anvil Lighthouse. Looking on your map, you should have seen a small islandwest of anvil. Swim there..
The Fin Gleam helm is just west of the island itself, not too far away. Look for the large rocks and there will be a skeleton hidden in between a large rock and a small rock. Now this takes a lot of diving, but it is worth it.
First you must first fast travel to the Anvil Lighthouse. Looking on your map, you should have seen a small islandwest of anvil. Swim there..
The Fin Gleam helm is just west of the island itself, not too far away. Look for the large rocks and there will be a skeleton hidden in between a large rock and a small rock. Now this takes a lot of diving, but it is worth it.