The automotive industry worldwide is the largest single market for fluid sealing components and in particular for rotary shaft seals. It is not surprising then, that most seal manufacturers have something to offer for the most popular applications - engine and transmission seals for passenger cars. The truck and bus sector requirements are slightly different, especially with wheel seals where very high mileage is expected between bearing and brake overhaul. For this reason unitised hub seals have made a big impact and are now essential for modern trailer fleets. We show 6 variations all requiring special installation tools. They are usually in Nitrile material and inch sizes but there is an increasing demand for Viton and metric sizes.