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

Although it may look delicate in photos, this spring is extremely reliable and does the job well. I was concerned about its size and weight transfer from my 100 pound bag, but after getting it and installing it I have no more questions about it. I used it in combination with a ceiling mount and wanted something between the bag and the roof to transfer momentum. This spring has definitely done its job. It also doesn't stretch or sag, and the twisted holes at each end give me a sense of security that the whole thing won't "pop out" and fall on me.