This collar is woven with 425 Paracord. These handmade collars not only look cool but are designed to last for years.  For those not familiar with Paracord, it is very durable and strong. The 425 means it is tested to 425 lbs of pull strength. My leashes and collars will hold up to very strong and feisty dogs - I've tested all my designs while walking dogs at a local German Shepherd and Belgian Malinois rescue, my last German Shepherd, and my pet sitting clients.