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KS3 Cobra Bag - Core Kit

KS3 Cobra Bag - Core Kit

Regular price ₩411,000 KRW
Regular price Sale price ₩411,000 KRW
Sale Sold out

The Kewlus Cobra Bag is the world's first modular cobra bag capable of customisationsadd-ons, upgrades and DIY integrations. Components just click together, so it's fast and easy to put up and to put away. It is the only cobra bag that is easily portable. Every component has been designed using 3D software and manufactured using advanced materials for ultimate strength and reliability. Most importantly each component can be individually upgraded when a new version of it is released. This cobra bag is part of the new type of modular training system that will continue to evolve, so your investment is well founded.

The Core Kit

The Core Kit is for those who who want to make their own sturdy base by simply gluing together a number of MDF boards or chipboards. This type of setup can provide more rigidity in the base compared to using the Platform Paddles, offering better performance. Please check out the Advanced Base Setup that is more suited for experienced boxers and is the one used by professional boxers like Tim Tszyu and the Irish Champions, Aaron and Stevie McKenna. For extra speed and rigidity, grab the Red Bar and the Olympic Sleeve as add-ons.

If you want a complete, free standing cobra bag that includes the platform (Platform Paddles and Sandbags), please check out the KS3 Cobra Bag - Free Standing.

The KS3 Spring

The KS3 Spring is the third generation Kewlus Cobra Bag Spring. It is made from a special type of steel, designed to withstand heavy punishment without breaking. It comes with alloy connectors, each having two adjustment points. The KS3 Spring can also be inserted directly into the Multi Base, giving you an alternative shortened version of the cobra bag (minimum height just over 3 foot) - ideal for smaller children, or for mounting horizontally, or even upside-down.

Important: Before using the KS3 Spring, please read the KS3 Spring Maintenance Guide.

The Base Connector

The Core Kit includes the amazing Kewlus Base Connector which can be used to support the cobra bag in a number of different ways:

  • Screwed into the floor such as a concrete floor in a garage or a wooden outdoor deck using 8 suitable screws;
  • Used with Platform Paddles (optional add-on) and weighed down with sandbags (optional add-on) and/or other weights;
  • Screwed to a DIY baseboard (not included)  and weighed down with sandbags (optional add-on) and/or other weights;
  • Used with 2 suction cup handles (optional add-on) on a smoothly painted garage floor (see details below).

The Base Connector comes with a stainless steel hose clamp. Once the Click Mast is inserted into the Connector it's important to tighten the clamp around the Connector collar as much as possible. 

Detailed & optimised base setup instructions are on this page:

What's Included in the Core Kit

The Cobra Bag Core Kit includes the following:

  • Kewlus Spring (KS3) is the 3rd generation Kewlus spring that fits onto the Click Bars and is also compatible with 3/4 inch pipes for DIY setups.
  • Max Power Genuine leather cobra ball, designed to fit perfectly onto the Kewlus Cobra Ball Adapter and made from genuine leather for handling maximum power;
  • Kewlus Cobra Ball Adapter (V2), designed to be used with most speed balls but is the perfect match for the Kewlus Cobra Ball. One unique feature that's not found on other cobra bags is it allows the user to extend the length of the top section, thus increasing the reach of the cobra bag;
  • 2 x Kewlus Click Bars - one goes above the spring and one below. These are made from light, yet strong aluminium which will not rust, with dual push buttons at each end. They are a key part of the modular click-and-go system;
  • Kewlus Click Mast (V2) - designed to simply click into the Multi Base for quick and easy removal and storage of the cobra bag. Made out of strong aluminium it will never rust. The bottom Click Bar simply slips into this mast and clicks in place at the desired height, giving you a height adjustable cobra bag suitable for both kids as young as 8 and adults as tall as 6 foot;
  • Kewlus Base Connector - super strong, minimalistic connector made from composite fibre. It's designed to be used in multiple ways, such as with a baseboard, with Platform Paddles, with Suction Cup Handles or simply bolted to the floor. It comes with a stainless steel clamp for the collar to lock the mast in place for the ultimate rigidity.
  • Kewlus Sandbags - these come as a set of 2, and are specifically designed to have the right capacity, so that when fully filled with sand or gravel they will give you enough weight for a stable platform. For extra weight I recommend using a plastic bag liner and filling them with wet sand.

The idea is to be able to swap as well as reutilise components as new add-ons are released. Check out my Youtube channel and stay tuned for more that is to come!

"When you purchase the Kewlus Cobra Bag Kit, you're not just buying a high quality cobra bag. You're investing in an upgradable, expandable and customizable fighter training system that is set to continue to grow and expand, with new components and add-ons due to be released in the coming months. You'll see from my videos that I'm totally committed and passionate about creating new and innovative gear. Your support will help me to develop and release more great and affordable add-ons and upgrades as well as new, innovative training gear for boxing, MMA and other martial arts."
Reedy Kewlus

Height Range

The height range of the cobra bag is roughly 4'8 (143 cm) - 5'7 (171 cm) from the floor to the top of the bag when using a 1.5 inch baseboard. If you wish to increase the height, consider making a 5-inch tall "Stubby" baseboard (see details and video:

Convertible To Short Form

The KS3 Cobra Bag can be converted to a shortened form (KS3 Spring plugged directly into the Multi Base), making the height range roughly 3'3 (100 cm) - 3'7 (110 cm). The shortened form is ideal for smaller children or for mounting upside-down from the ceiling or horizontally on a wall.

Optional Accessories & Add-Ons

Check out the Accessories section for optional accessories and add-ons such as:

  • Max Speed Cobra Ball & Adapter Combo - switch to a lighter and faster ball mid-session;
  • Genuine Leather Boxing Gloves - grab a pair of these genuine leather boxing gloves to get the most from your cobra bag training sessions;
  • Hand Wraps - use a pair of handwraps to absorb the sweat and protect not just your hands, but your gloves as well.
  • Suction Cups (Limited/Varied Usage) - these come as a pair and can be used on painted concrete flooring, such as in a garage to hold down the Base as a possible alternative to the Platform Paddles. They can be also used for mounting the shortened version of the cobra bag on a vertical surface. Please note that these suctions cups do not work on all surfaces, and even on smooth tiles are likely to dislodge with heavy punches. I cannot guarantee that they will work on the surface that you choose. Failure to stick to your floor or wall surface does not qualify for a refund. See the Suction Cups product page for set-up instructions and a demonstration video.

Assembly & Optimisation

Make sure to check out the Kewlus Cobra Bag assembly instructions and optimum setup tips: How To Set Up Your Cobra Bag Kit.

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.


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 40 reviews
Victor V.
KS3 Cobra Bag

I love this Reflex Bag! The Kobra Bags from Reedy Kewlus have come a long way! I remember using the red spring with total DIY equipment. This new one is the best. Its perfect and I love it. Thank you Reedy Kewlus for making an affordable Reflex Bag!

Khalil S.
Great product

Good support and Service

Daniel D.

Exactly what I wanted, was a bit concerned with it being click together but shouldn't have been, very well engineered and well worth the money.

Ozhan A.

The only think I would wish for is slightly heavier ball. It would be amazing if I could buy a different ball for different work purposes. Like keelus XL ball, because I love working with 16 oz on cobra bag and double end bags, having a slightly bigger ball (probably not more than 3 oz heavier) would be great

Thank you for the great review and the feedback. Try taping some wide electrical tape or duct tape (stretchy type of tape) around the base of the ball - it will add extra weight and strengthen the ball in that area at the same time. The more tape you wrap, the heavier it will get.

Brett M.
Worth every penny

I had been shopping around for a decent cobra bag and stumbled across the KS3. The quality is fantastic and the spring gives a higher end challenge than any other pieces of equipment in the same price range.

Miguel M.
KS3 Cobra Bag

I'm very happy with my purchase of KS3 COBRA BAG, the material is very good and strong is made it to last a lot of years...
Amazing workouts 🥊🥊🥊
I love it.