1、Fitment: Trailer bearing dust cups are fit for 2000 to 3500 Lbs trailer wheel hubs, please confirm whether your model is applicable before placing an order. 2、Bearing Protecting: The dust cap can protect the bearing from the intrusion of dust, particulate matter and other pollutants, extending its service life. 3、Practical: Trailer bearing dust caps reduce maintenance costs by preventing external substances from entering the bearing, reducing the need for frequent cleaning and lubrication. 4、High Durable: Trailer bearing dust caps resist harsh environmental, such as in dust, moisture, which enhances bearing reliability and durability in tough conditions. 5、Easy to Install and Use: The 4pcs trailer axle grease caps have a simple design that makes it easy to install to the trailer wheels and doesn't take long.