A retractable leash comprising a housing (20) comprising a casing with a hand grip (21) and where inside the casing there is a wheel winder (22) intercepted by a brake mechanism which uses a pusher cam (24) rotating on a pin (29), fitted with a brake pad (25), where the brake mechanism is operated by a button (23). The cam mechanism (24) enables braking of the self-triggering type and the locking force is inversely proportional to the braking force and the mechanism operates according to the friction ratchet principle.
