The sealing in these Permanent Magnet Water Pumps(https://www.solarpump-factory.com/product/permanent-magnet-water-pump/) typically relies on mechanical seal assemblies rather than traditional packing seals. These mechanical seals consist of precision-engineered components such as silicon carbide, graphite, or ceramic faces that rotate and slide together under hydraulic pressure to prevent leaks. They are known for providing a tight seal even under high-speed and high-temperature operating conditions.