This is the most common shape for municipal sewage systems.

• The "Safety" Sell: Circular covers cannot fall through their own openings (unlike squares), making them the safest choice for deep manholes.

• Traders' Advantage: They are easier to move and maneuver on-site by rolling them, which reduces labor effort.

• Applications: Main sewer lines, water hydrants, and heavy-traffic intersections.

These are preferred for construction projects involving tiles, bricks, or pavement.

• The "Alignment" Sell: They align perfectly with the "lines" of a sidewalk or a building’s foundation, making the installation look clean and professional.

• Traders' Advantage: Easier to stack and transport in bulk on standard pallets compared to round shapes.

• Applications: Telecommunications (fiber optic pits), electrical junction boxes, and residential drainage.