RockShox Dropper Post Lower Sealhead Foam Ring Description: The RockShox Dropper Post Lower Sealhead Foam Ring acts as a line of defense to prevent contaminants from getting into your dropper seatpost and mucking up the internals. If you have multiple bikes with a Reverb dropper post or if you are regularly servicing your seatpost, this 10 pack of the lower sealhead foam rings ensures that you will have the parts on hand when you need them. Features: Includes 10 separate foam rings for servicing the lower sealhead of the Reverb dropper seatpost. Specifications: Compatibility: 2020+ Reverb AXS/Reverb Stealth A1-B1