Ronstan Constrictor relieves TC single 6mm rope

Unlike conventional relievers, the Constrictor® does not clamp the rope between two metal surfaces. Instead, the rope is held securely in a textile sock,
which itself is attached to a base unit. The rope runs freely through the stocking in one direction, but is immediately caught when it runs out into it
opposite direction. This patented ?constrictor effect? provides greater holding power when the load increases.