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KS2 Cobra Bag Spring

KS2 Cobra Bag Spring

Regular price ₩44,000 KRW
Regular price Sale price ₩44,000 KRW
Sale Sold Out
Taxes included.

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 roughly 12 inches (30cm) long and designed to fit easily onto a 3/4 inch pipe and simply held in place with strong duct tape. Increase the speed by moving the spring lower onto the pipe, thus reducing the number of active coils.

Please note that trying to adapt the Kewlus Spring to another cobra bag of a different brand is unlikely to work due to important parameters such as the spring diameter, as well as the length and weight of the top section of the bag. Heavy top section bags will result in slow performance.

Limited Time Offer: Get 30% Off

Use the code REEDYKEWLUS at the checkout to get 30% off the KS2 Spring! This is a limited time discount and is limited to one per customer.

DIY Instructions

For complete DIY build instructions including a video using the Kewlus KS2 Spring (used to be known as the 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:

KS2 vs KS3 Springs Compared

Check out this article to read about the differences between the KS2 Spring and the KS3 Spring, or watch this video:

 

Shipping Info

USA & Canada

USA and Canadian orders will be shipped from Canada and takes just 2-3 days to most locations. Shipping is calculated at checkout.

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 3-5 days. NZ orders take 7-14 days. Shipping is calculated at checkout.

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. Shipping is calculated at checkout.

Please note that you may need to pay import tax in some countries outside of Canada, USA, Australia and New Zealand. 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.

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Customer Reviews

Based on 33 reviews
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(29)
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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
Ak
Spring Only Purchase - Good

Overall, Spring reflex action is good but DIY build can be improved. Some of this could be be me but want to share issues I ran into during build.

1) Finding a 3/4 & 1 Inch metal pipe that fit between each other is tough. I tried HD, Lowes, Menards, etc and didn't have success. I spent 3-4 hours using hammer and sanding tools/brushes to make things bit more manageable.

2) Butterfly clamps are good but need something more sturdier. Jabs are great but if you plan to mix Jab with uppercuts you might send the pvc pipe flying upwards. I have to hold back power on uppercuts to overcome this issue. My thinking is that better or more clamps are required to overcome this issue.

3) I have no vibration or sound when I use the bag which is great. If you pay close attention to the build it should be mostly sturdy.

4) I did not build circular base and choose rectangular shape so I could put two 55 lbs plates (total 110 lbs) on the base. I attached flange to a rectangular shape pressure treated wooden board (approx 1.5 inch thick and 10 inch by 40 inch). I am realizing circular base would be better. I will rethink this later.

5) Note, with amount of time spent to get the metal pipes to fit in one another and $'s spent (Metal Pipes, pvc pipe, flange, pvc connector, butterfly clamps, bag, spring, duct tape, funnel, screws, and wooden board), I would highly recommend just buying the whole kit vs spring. Now, if you have some of these things at home already, then you may find it beneficial to buy spring and build. This was not the case for me.

Lastly, let me just point out that the bag is so much fun. I have gotten smacked in my face a few times but still enjoy very much. Thank you

A
Arturo A.
KS2 Spring

Incredible product, if you follow all the steps on his website and YouTube demonstrations, you will succeed in making your DIY cobra bag. Thank you Reedy and team for sharing your love and creativity with the boxing community!

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.

E
Erick S.
save yourself some money, HIGHLY recommend

The spring works amazing, and following your youtube tutorial made it super easy.
The homemade version is about 200 dollars cheaper then the cheapest cobra bag, and is better in every way due to how much adjustment you have. Like stated in your video, having everything be modular makes it so nice if I want to change out the bag, or if something breaks in the future. Highly recommend