This large-size heavy-duty punching bag spring is designed to reduce noise, absorb shock, and increase the lifespan of your punching bag setup. Built from high-grade steel with tightly-wound coils, it provides smooth rebound action for boxing, kickboxing, Muay Thai, MMA, and fitness training. Ideal for gyms, dojos, and home setups, it minimizes stress on ceiling mounts, chains, and brackets while ensuring a safer and quieter training experience. Compatible with all heavy bags, banana bags, wrecking balls, and double-end systems.