How can it tighten/release the opposite way to the lock ring, is it double threaded?
The diameter of the lockring is smaller than the cog, so the screw threads are entirely separate.
The threading on the left of the pic below will take a cog + lockring; the threading on the right will only take a cog:
@mattty started
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The diameter of the lockring is smaller than the cog, so the screw threads are entirely separate.
The threading on the left of the pic below will take a cog + lockring; the threading on the right will only take a cog: