The Redline K-9 Extreme Bungee Line is built for Heavy Duty Dogs! The Extreme Bungee consists of two 5/8" lines combined for a total of 1-1/4". Used by many of the top trainers in the dog sports, bungee lines offer many unique drive building methods for young dogs to seasoned adult dogs.But these aren't your average Bungee lines! The Redline Extreme Bungee lines are made for the heavy hitters. And just like our standard bungee lines our extreme bungee lines are unique and superior to many other bungee lines on the market. We have a special manufacturing process that takes the high quality shock cord and inserts it inside tubular webbing. The webbing is then bunched up to allow the line to stretch out and knotted off with the shock cord. Nylon webbing color may vary.No More Loops and Clumsy Hooks for You and Your Dog to Tangle Up In!How far will your bungee cord stretch? The rule of thumb with bungee cord is that it stretches approximately 50% of it's dormant length. For example, a 7' bungee stretches to approximately 10.5' feet.