Above the newer type click spring.
The "J16" is not mentioned in any catalog or part list to my knowledge. Junghans documents only show that it had an internal used name J14 and it was sold to Alpina which named it Alpina 225. Alpina only got movments with a detached escape-wheel cock which would make it a J16/1.
The J16 can be found with two different used clicksprings.