Best bet is to contact Dahon:

https://usa.dahon.com/pages/contact-us

The Boardwalk is Dahon's longest-running model. Debuting in 2000, it's still in production. It has received spec upgrades over the years (notably moving from hi-ten steel to chromoly) and been supplied as single-speed, derailleur geared and with hub gears. It has quite a following in some parts of the world with model-exclusive clubs and rallies.

Boardwalk meet-up in the Philippines


Boardwalk owners on tour in Malaysia