Push Toggle rear brake on Cunningham #33C "the land access bike"

TD,
Built like a Swiss watch, one at a time.
The better you can stop, the faster you can go. Charlie Cunningham's one finger brake.

In Charlie's own words, this was the ultimate brake in terms of function: incredible power, great modulation, and very light action. But it was also very difficult to make and to set up so only 6 bikes got them and only a couple have adjustable turnbuckles.