1 2

Kewlus DIY Cobra Bag Spring (KS2)

Kewlus DIY Cobra Bag Spring (KS2)

$29.00 USD
$35.00 USD $29.00 USD
Sale Sold out

Save a ton of money by making your own DIY Boxing Cobra Punching Bag with the KS2 Cobra Bag Spring. Increase the speed to your liking, yes with the KS2 the 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, click here.

Cobra Punching Bag DIY

Reviews & Build by Others

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:

Here's a video of the spring in action (DIY bottom section and base) posted by a customer:

Shipping Info

Shipping is calculated at checkout with the following average shipping times.

USA & Canada

USA and Canadian orders will be shipped from Canada and takes just 2-3 days to most locations.

Limited Time Special Offer for USA customers: Orders to USA & Canada over $100 USD get free shipping.

Australia & NZ

Australian orders will be shipped from Queensland and takes just 2-3 days. NZ orders take 7-14 days.

The Rest of The World

All of the orders for the rest of the world are shipped from Canada and takes around 1 week to deliver.

Please note that you may need to pay import tax in some countries. Please check with your country's importation laws to find out how much tax would be charged.

Tracking 

You will receive an email with a tracking link as soon as your order is shipped from the warehouse. Please note that orders are not shipped on weekends or public holidays.

Pre-Ordering Products

Some products are available to pre-order and receive as soon as the are in stock. Please note that if you order these items together with other products, you whole order will not be shipped until every item in your order is available. All items in your order will be shipped together at the same time.

View full details

Customer Reviews

Based on 15 reviews
73%
(11)
7%
(1)
7%
(1)
0%
(0)
13%
(2)
100.0
100.0
G
Greg S.
Perfect addition to DIY setup

Hey Reedy, Yes, so glad I sprung for the KS2 Spring and definitely the added KS2 Spring Caps.
Made a tremendous difference from when I started with just the 3/4 inch PVC pipe alone. That was NOT working for me. The solo PVC had Very little spring and continuous bounce for sure.
Will try to send pics of final
Product. Going to buy a Coupling to add 4 inches now and have really fast Cobra bag and one slower bag without changing height OR compromising the Spring longevity.
Did get whacked in face a few times, but that's the learning process.
Thanks for ALL your videos that helped tremendously with the build. And of course a "shout out" to "cssquaredboxing" videos for all his videos and input where he always mentions Kewlus. Com

A
Anonymous
Cobra Bag Spring

Incredibly well made, very sturdy and amazing customer service.

A
Austin
Great spring and intro to DIY

Thank you Reedy! This spring is great, and I can't wait to upgrade when I get better at boxing!

R
Rob O.
Ks2 setup

An unbelievably simple , cost effective idea that can be easily tweaked to your personal preference.
It’s so much faster and more responsive than the store bought ones. And the whole setup can be made for under $100
One happy customer here

L
Luc V.B.
So far, so good

I have the gordex reflex bag. Which is, in my option a good bag. Unfortunately the spring broke on me. So I decided to purchase Kewlus cobra spring. I tack welded it on and been impresse ever since. Would purchase again if need be

p
pedro m.
Cobra product

The quality of kewlus products are amazing. Definitely takes some abuse. The leather feels really good. Putting it together everything was super easy And you can Tailor it To your body type. You can buy extra PVC and galvanized steel pipe So you can tailor it to kids or wife. Definitely recommend kewlus products to any body looking for high quality boxing equipment.

Load More

Customer Reviews

Based on 15 reviews
73%
(11)
7%
(1)
7%
(1)
0%
(0)
13%
(2)
100.0
100.0
G
Greg S.
Perfect addition to DIY setup

Hey Reedy, Yes, so glad I sprung for the KS2 Spring and definitely the added KS2 Spring Caps.
Made a tremendous difference from when I started with just the 3/4 inch PVC pipe alone. That was NOT working for me. The solo PVC had Very little spring and continuous bounce for sure.
Will try to send pics of final
Product. Going to buy a Coupling to add 4 inches now and have really fast Cobra bag and one slower bag without changing height OR compromising the Spring longevity.
Did get whacked in face a few times, but that's the learning process.
Thanks for ALL your videos that helped tremendously with the build. And of course a "shout out" to "cssquaredboxing" videos for all his videos and input where he always mentions Kewlus. Com

A
Anonymous
Cobra Bag Spring

Incredibly well made, very sturdy and amazing customer service.

A
Austin
Great spring and intro to DIY

Thank you Reedy! This spring is great, and I can't wait to upgrade when I get better at boxing!

R
Rob O.
Ks2 setup

An unbelievably simple , cost effective idea that can be easily tweaked to your personal preference.
It’s so much faster and more responsive than the store bought ones. And the whole setup can be made for under $100
One happy customer here

L
Luc V.B.
So far, so good

I have the gordex reflex bag. Which is, in my option a good bag. Unfortunately the spring broke on me. So I decided to purchase Kewlus cobra spring. I tack welded it on and been impresse ever since. Would purchase again if need be

p
pedro m.
Cobra product

The quality of kewlus products are amazing. Definitely takes some abuse. The leather feels really good. Putting it together everything was super easy And you can Tailor it To your body type. You can buy extra PVC and galvanized steel pipe So you can tailor it to kids or wife. Definitely recommend kewlus products to any body looking for high quality boxing equipment.

Load More