Material: Traditionally made of cast iron or ductile iron; modern covers may also use composites or concrete.
Weight: Heavy enough (typically 50–100 kg) to stay in place despite traffic, but still removable by workers.
Surface: Often textured or patterned to prevent slipping.
Locking system: Some have locking mechanisms for security and to prevent unauthorized access.
Functions:
1. Protects underground utility chambers from accidents, theft, or damage.
2. Ensures safety of vehicles and pedestrians.
3. Provides easy access for inspection, maintenance, and repairs.