Hi there—

I scored an old Brompton cheap. The prior owner says it was 15 years old, and it seems to have seen regular maintenance— it was originally 5-speed, and still has a 5s shifter, but now has a 3 speed BSR hub. It also has a dual-pivot front brake which may have been upgraded at some point? What model is it? And what would I need to do the locking rear wheel mod?

Here it is as I bought it:


And here it is after a new saddle and making some new mudflaps from sheet rubber: