Round gully grid drain covers are typically constructed from robust materials like cast iron, steel, or reinforced plastic. These materials are chosen for their versatility, strength, and resistance to corrosion, ensuring that the covers can withstand heavy traffic loads, harsh weather conditions, and the wear and tear of urban environments. The design is often round, which is advantageous because it distributes weight evenly, reducing the risk of cracking. Additionally, the round shape prevents the cover from falling into the gully, unlike square or rectangular designs, which can be inserted into the opening in a way that allows for potential accidents.