Update your semi with enhanced axle protection and lubricant leakage prevention, with the National 370036A Red 37 Series Wheel Seal for 19,000 lb Trailer Axles that ensures you're Ready for the Road Ahead™. This replacement kit snugly fits inside the hub assembly, preventing contaminants from entering the wheel and preserving the lubricant. Engineered with weather and heat-resistant rubber for optimal performance and durability in harsh conditions. FleetPride is your First Click in Heavy Duty®.