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FourSide Jar


When it came out, the FourSide jar set new trends in commercial blending. It was only natural that it became a hit with consumers around the world.

FourSide Jar is rated 3.8 out of 5 by 99.



3 years



  • BPA-free FourSide jar
  • Vented Latching lid

The Original Square Jar

The FourSide jar effectively harnesses the power of your Blendtec blender. Its blunt safety blade is thicker and stronger than other blades. It is made from impact-resistant, BPA-free copolyester and is compatible with all Blendtec consumer blenders.

Better Blends

The FourSide jar’s square shape blends much better than traditional round jars. The jar also generates more friction, heating soups and hot drinks quickly and easily. It’s also especially good for grinding grains and making smaller quantities.


  • Capacity: 75 oz with measurements up to 32 oz
  • Jar Dimensions: 5.37'' wide x 9'' tall x 5.37'' deep; 3.88'' wide/deep just above the base
  • Shipping Dimensions: 7'' wide x 9.5'' tall x 7'' deep
  • Weight: 1.5 lbs
  • 3 year warranty


Rated 2 out of 5 by from Poor blender jar design I've had a kitchen champ for 21 years, on my second one. I really like the machine and the blender, but the blender jars are worthless. They are fine when they work, but the rubber gasket eventually shreds and seizes up or the barrings must go and it won't turn properly and sounds funny. You used to be able to send them in and they would fix them, but now they make you buy a whole new one and throw the bad one out. I have gone through A LOT of blender jars and am getting tired of forking over 100 bucks all the time. I am thinking about switching to a vitamix because this is getting ridiculous. Very poor design and customer service isn't the greatest either.
Date published: 2017-07-06
Rated 3 out of 5 by from 5 stars for base, 0 stars for jar I've had my old K-tec Champ since 1996. It runs beautifully and makes short work of almonds, spinach, berries and anything else I put in my smoothies. However, my 4th jar just bit the dust. The first jar lasted for several years, but I didn't use it as much then. The last three have lasted for about 2-3 years each. This one is just over 3 years old. I don't want to spend the money for a VIta-mix when i have a base that works so well, but this jar issue is ridiculous. I'm going to just start using the warranty at 2 years and 11 months even if the jar isn't show problems yet. BLENDTEC - YOU HAVE TO FIX THE BEARING ISSUE ON THE JARS!!!
Date published: 2017-10-18
Rated 4 out of 5 by from Excellent Blender, Poor Bottom Gasket I love this blender, but am put off by the poor life of the container given that after about 300 cycles the blade does not spin freely. I clean and maintain it regularly, so I feel cheated. I clean it even better than the manual suggests so this shouldn't be happening. I am the only user, so there is no way somebody could be tampering with it or abusing it without my knowledge. It would be great if this blender had a kit to change the gasket at the bottom. THIS WOULD SET THIS PROBLEM TO REST AND LOCK IT IN AS A '10'. I don't think the competition does this. Nudge! Nudge!
Date published: 2015-10-30
Rated 3 out of 5 by from Works great, but not for long I've been using these for over 10 years and blend about 4 times a week on average. The contents range from yogurt and fruit smoothies to heavier items like meat and vegetables. We only fill the jars to about 24 - 30 ounces and get absolutely perfect results every time with only a single blending cycle (50 seconds). However, they only last about 1-1/2 years before the seal fails and the blade doesn't turn easily. Always slightly past the 1 year warranty, of course! But as long as the blender keeps working I guess we'll keep buying the jars.
Date published: 2015-05-04
Rated 3 out of 5 by from Grinding sugar into powder I love the blend! Just wish you had a feature that I could use to help me grind my sugar into powder. It does a fantastic job except now the container leaks causing the plastic on the bottom around the impeller melted. Due to the friction in the grinding process because the sugar is so hot when grinding. Is there a container that can help me grind my sugar? It's one of the key ingredients in my chocolate business. Please help me. I only had the blender for few years maybe 2 years and just start my business a year and I already need a new container.
Date published: 2014-08-19
Rated 1 out of 5 by from Bearings don't last, making jar worthless! I'm on my 5th jar, and the bearing go out quickly. The last jar lasted less than 500 cycles, so that's $.12 in jar cost every time you hit the start button. The blender is fantastic when the jars work, but they don't work for very long, and are expensive to replace. It shouldn't be that hard to find a quality bearing that will work in the jars for more than 500 cycles.
Date published: 2015-07-21
Rated 2 out of 5 by from Rubber on bottom of jar wears out too quickly I bought my K-TEC (company's old name) blender in 2003 since it was the strongest on the market. It works great still. I only use it about 2 times a week to make smoothies. The problem I keep having is that the rubber on the bottom of the jar keeps wearing out every 2 yrs or so. The warranty is for 3 yrs., but it never makes it that long. They did replace my prior one for free, but the new one wore out in 1&1/2 yrs and I have to now pay for a new one. So, the replacement didn't come with a warranty. Can't something be done about the rubber seals? Plus, you have to buy a whole new jar, not just the seal. Not cheap & a waste of plastic that's still all good. They did give me a small discount, but still cost a lot. I have done all the company has suggested in the way of taking care of the jar, such as turning the drive shaft, keeping it clean and I always hand-wash it. My rating is for the jar only.
Date published: 2015-04-28
Rated 5 out of 5 by from Love the Four Side Jar! I bought my Blendtec with the Wildside Jar on sale at Costco last year and, while I have loved the operation of the blender, sturdiness and ease of cleaning, the bigger jar wasn't designated for some of the recipes and smaller amounts I wanted to use. Since getting the Four Side jar, I find I use it all the time with all the recipes I want!
Date published: 2014-07-30
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Is this Jar suitable for a 2009 blendtec Serial # 14599

Asked by: Socorro
All of our jars will fit all of our machines.
Answered by: Blendtec Catherine
Date published: 2017-10-06

Why does the bottom rubber seal keeps leaking after a year? I may be switching to Vitamix even though I like Blendtec's design and functions. Is Blendtec going to come out with a newer model with better rubber seal?

Asked by: GerryM
Blendtec has come with a new design for the jar. You can check the warranty of your machine at jar when you call customer service at 800-748-5400.
Answered by: Blendtec Catherine
Date published: 2018-07-16

Is there a kit for replacing the bearings in the mechanism in the jar. The jar holds up but the mechanism does not.

Asked by: PamG
There is not a kit for replacing the bearings or the blade. Call customer service at 800-748-5400. You will need your serial number (from the bottom of the machine) as well as the engraved number on the bottom of the jar. They can check for warranty. If under warranty, they can replace the jar.
Answered by: Blendtec Catherine
Date published: 2018-07-16

I need a jar for my blender model Es3 EZ blender serial EZB36913.  Please let me know which one is compatible.  Thank you

Asked by: Trisha chung
Hi, contact the dealer that you purchased your commercial blender through. They should be able to help you with the purchase of a new jar.
Answered by: Blendtec Catherine
Date published: 2017-10-20

I need a replacement jar for my blendtec. The model of the jar is 40-505 and the blendtec model # is ES3 total blender black. I purchased the blendtec @ Costco.

Asked by: Charles M
Please call customer service at 800-748-5400. You will need the serial number of the blender (found on the bottom of the machine) and the number engraved on the bottom of the jar. They will help you with a replacement.
Answered by: Blendtec Catherine
Date published: 2017-07-28

how do i know this matches my base model CTB2?

Asked by: sarahfoxvi
All of our jars with fit on all of our motor base
Answered by: Blendtec Catherine
Date published: 2017-07-17

Hi blendtec ! I want to replace the jar of my " ES3 Total Blender". But, it is not clear that the FourSide jar meet " ES3 Total Blender". Is the FourSide jar compatible with Blendtec blender model " ES3 Total Blender" ?

Asked by: Ilovecat
Yes, all of our jars will fit all the home blenders. ES3 Total Blender is residential so you will have no problems.
Answered by: Cherrera
Date published: 2017-06-05

what is the warranty on this jar?

Asked by: melaneeo
The jars come with a 3 year warranty.
Answered by: Cherrera
Date published: 2017-03-14
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