Cantilever brake ID?

Hello! A customer at my shop brought in an absolutely gorgeous 90s Merlin that I've fallen in love with and it has a set of cantilever brakes on it, in a design I've not seen before. It uses two screws to secure the pad, upper one secures the toe and height of the bracket and the lower one secures the rotation of the pad. These are effortless and amazing! What are they!
Thanks!