I am having some J3 brake work done and the guy doing the work remembered a box of parts he had for a J3 he once owned. Finding the box there were J3 brake parts inside, but neither he nor I can identify the type or source of the brake cylinders. Some of the parts are new, and the brake cylinders appear to be a new piston/cylinder system replacing the diaphragm and back side of the Scott housing. I'm attaching photos. If anyone can identify the pedigree of these cylinders we would be obliged.