Dimensions: 37 x 50.5 x 5.6/12.8 TYPE Y-2ARIETE Fork Seals are manufactured using XNBR Rubber compound and Stainless Steel metal inserts with Steel tension springs. XNBR Carboxylated nitrile rubber is an improved version of NBR type rubber, XNBR combines the technical properties of nitrile rubber NBR but with an increased strength, higher abrasion resistance and a tolerance to chemical additives which are used in fork oils. All ARIETE* fork seal lips are Fine Ground Finished, which offers complete control of varying internal pressures during extension and compression of the Fork. Ariete Fork Seal Set - Comprises of 2 x Premiun M/C Fork Seals and 1 x Sachet with special Arisil grease which helps to increase the life of the seal.