The STD series (standard type) has the same quality as the specs in the market. The price range emphasizes on cost performance is also attractive. As the name of the OR series (oil resistant) and OR(OIL Resistant), the STD type has been given an oil resistant properties. It has excellent anti-inflation in mineral oil and silicone oils, and is made to satisfy users who want high performance that will maintain its well-finished damper performance for a long time.