The bell-mouth design of bi-metallic lugs provides great benefits for ease of installation and cable protection. A flared, or bell-mouth, entry in the aluminium barrel of the lug is designed to direct and facilitate the insertion of conductors, particularly in the case of stranded or fine-stranded aluminium cables. The funnel-shaped, smooth entry ensures that the strands of the cable ... https://www.pioneerpowers.com/bimetallic-lugs-and-connectors.php