Suspension block set complete - includes bolt and disc

This is the complete Brompton suspension block assembly complete with bolt and fittings

Until 2017 there were two levels - standard and firm - which one was used was based upon rider weight and prefered riding style. Now there is only one.
Suspension is important on small wheeled bikes such as the Brompton.
The suspension on a Brompton is provided by a polyurethane block mounted between the main and rear frames.
Lightweight and effective, it smooths out the lumps and bumps and helps to avoid excessive bounce.

(Tip: To stop the suspension block creaking/squeaking when you ride - put a good quality grease on the bolt which runs through the middle)