This item is a bimetallic cable lug, specifically a DTL-2 model designed for transitioning between aluminum cables and copper terminals.
The barrel is made of aluminum, intended to crimp a cable with a cross-section of 35mm2.
The ring terminal is constructed from copper to ensure a high-conductivity connection to a bolt or busbar.
These connectors are commonly used in power distribution systems to prevent galvanic corrosion when joining different metals.