Unlike all conventional clutches the Constrictor® system does not crush the rope between two metal surfaces. Instead, the loaded rope is held securely in a textile sock, itself attached to an anchor base. The rope runs freely through the sock in one direction, but is gripped instantly within the sock when running out in the opposite direction and can achieve a holding power equivalent to the breakstrength of the rope it is retaining. This constrictor effect, patented by COUSIN Trestec, provides increasing holding power as the load increases. The Cousin Constrictor® has 2x the holding power, with zero abrasion and 1/3 of the weight of conventional rope clutches. It can easily be released by hand under load, either locally or the system can also be adapted for remote release.

The Flush mount option replaces the annoy base unit with alloy mounting collar, designed to be mounted on a suitably reinforced bulkhead of a customised base fitting.