Brompton seatpost bumper O-Rings (Pair)

These O-rings go around the top of your Brompton's seatpost right beneath the pentaclip, and they serve as a nice bumper to keep your pentaclip from smashing into your painted main frame when you quickly collapse the seatpost. If yours are worn out or missing, or your bike just doesn't have them, get a pair of proper replacement O-rings.

Standard and Extended seatposts normally use two O-rings. Older versions of the Telescopic seatpost typically used one O-ring on the upper seatpost. (see the relevant instruction page) Current Telescopic seatposts do not come with an O-ring, presumably because Brompton has made the black plastic insert stand slightly higher to try and do the job of the O-ring. Given the choice, we still like to add an O-ring to the modern Telescopic posts.