Review on Ringside Heavy Duty Bag Spring: Ultimate Boxing Training Accessory (Up to 150 pounds) - Gray by George Miller

This is a spring. It was designed to perform only two functions - stretch and recoil. I found it does the job as well as one would expect. Functionally, it's incredibly heavy and handles my heavy 100-pound bag with ease, even hanging my 145-pound body from the attachment straps. My bag has been hanging on the spring for about 2 months and I have worked with the bag many times but the spring looks and works just as good as the day I installed it.