Great product
The factory outer seal doesn't really prevent mud/water/dirt etc from going into the axle housing. Once it did, it sped up the failure of the inner axle seals. When you purchase these, they will keep out the water/dirt and you won't have to worry about pre-mature inner axle seal failure again. Super easy to install and grease them periodically when you're in for a service/doing one yourself. Great product I highly recommend these.