Very good with durable cord and many adjustment options (stop in one position by holding down the button, stop in one position with lock so you don't get tired and free to adjust). And lastly, which is very important to me in terms of safety, when it is locked in one position and you unlock it while your dog is pulling at that moment, it doesn't unlock! You have to loosen it a bit and not have it stretched and it will unlock. Just be careful with the sand from the sea because the mechanism can be damaged if sand gets inside.