The WDN Scraper is one of the simplest Snap in type Wiper Seals (similar to WDD style of Wiper Seal, but with diff erent groove dimensions), mostly suggested to be used in conjunction with a back pumping Primary Seal/Secondary Seal, like TRITILT® (RSS type) Seal. The Inner Lip holds the fi lm of oil within the system without being leaked out and the Outer Lip shall prevent any dust particles entering the system.