Kewlus Spring KSR12PRO

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  • Regular price USD $49.95
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Make the ultimate and fastest Boxing Cobra Punching Bag with the ultimate Kewlus PRO Spring: the KSR12PRO. Increase the speed to your liking, yes speed is adjustable! This spring is designed to fit easily onto a 3/4 inch pipe and simply held in place with a butterfly hose clamp. Increase the speed by moving the spring lower onto the pipe, thus reducing the number of active coils.

DIY Instructions

For complete DIY build instructions including a video using the Kewlus PRO Spring, go to

Cobra Punching Bag DIY

Review & Build by CSquared Boxing

Check out one of the top boxing gear reviewers on YouTube, Carlo Rosauro to see his hands on take on the spring as well as his full build 

Kewlus PRO Spring Review by CSquared Boxing

Kewlus PRO Spring Community

Check out the Kewlus PRO Spring Community page to see how others have setup the Kewlus PRO Spring cobra punching bag!

Customer Reviews

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