Reward | Mayan Stelae AC IV: Black Flag Guide

The Aztec bulletproof vest.

After you have obtained all of the stones, you need to go to Tulum to the door that you have visited with Kidd, on the North-Western side of the location. It is marked on the map. Approach the door and press B for Edward to start slipping the stones into the slots. In the room at the other side, there is a durable Mayan armor, impenetrable for bullets. After you put it on, Edward will be invulnerable to damage from pistols and muskets.

Note! You will not be able to obtain the armor until you complete mission 2 of the 11th sequence because, only then will you be able to roam around the Caribbean freely, and you will be able to go to Tulum.