NTR Zipline Spring Brake,Brake Zip Line, Zip String 6.6FT Extra Long High-Strength Compression Stainless Zip Line Spring, Steel Ziplines Brake, Zipline Brake System/Stop/Stopper, Zipline Parts. Our one piece zipline spring brake can protect adults whose weight is within 350lb on the safe slope 2to 3 of the ground(drop rang 3%-5%).
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