A spring-loaded mechanism that throws a non-choking loop over the canines head which secures the animal; the tether holds them in place. The Collarum ACO Special is a safe and humane capture system. All stainless construction. The Complete ACO Special, comes with the following:- This kit includes a Field Guide and Collarum Setting Instructions that explain how to set the Collarum 1 Domestic Dog model Collarum (Stainless) 2 Cables; 1 primary and 1 replacement (both w/Relaxalock) 2 Rebar stakes for anchoring the Collarum cable 2 pegs for anchoring the Collarum baseplate 1 screw link on cable for easier transfer of canine 1 Prepared bait cap 1 (4 oz.) jar of Canine Specific Food Bait 1 Bait Spreader for applying bait 1 5ft. security cable for theft prevention This is a complete kit for capturing canines.