These Damper X-rings have X-shaped cross-sections and offer increased oil sealing effect compared to standard O-rings with circular cross-sections. Made from special silicone material, these X-rings also maintain their shape, and therefore their sealing ability, for a longer period of time. This makes them ideal for use with Aeration Dampers such as Item 42198 Buggy HL Aeration Damper Set and Item #54028 Buggy Aeration Oil Filled Damper Set. Item #42214 is designed for use with silicone damper oil while Item 42215 is for mineral based damper oil.