The clue is in the riddle if you get stuck trying to find this cache:
I am two and one, opposite yet wed —
One wears a crown of six, the other hides a bed.
One marches out with a spine wrapped tight,
The other waits inside, a dark spiral night.
When lovers court they spin in place,
Rightward embraces seal their grace.
I bite in silence, measure by thread,
Counting tiny stairs where none are tread.
I pass through flesh but leave no scar,
I pull things close though I’m small and hard.
My tongue is metal, my vow is force,
I follow the shortest spiral course.
Call me by a name that’s weathered and old,
By workshop lore and engineers bold.
I’m not a lock, yet I fasten fate—
A pair that mends wood, iron, and gate.
What am I that turns without a song,
Two-body marriage, neither weak nor wrong?
Solve me by thinking of crowns, of beds, of spun delight—
But know: the answer tightens in the right.