Designed to be aggressive with quality, reliability, and durability top of mind!

Swapping out traditional round wire combine concaves for our innovative bar-and-grate style modular MAD Concaves™ results in more efficient threshing, getting your grain out of the head and into the hopper quicker for decreased rotor loss and less dockage. This means higher quality crops and more money in your pocket.

In addition to increased quality and reduced loss, our fast and easy-to-change modular designs allow you to quickly swap out inserts in minutes. Therefore, you’ll save you valuable time, which is critical in a busy harvest season.


Maximize your combine’s performance efficiency. MAD Concaves are easy to change, which allows you to quickly swap out inserts in minutes and save valuable time. Our cutting-edge concave systems are designed to be aggressive. As a result, you’ll see reduced dockage and losses for higher quality and better returns.


MAD Concaves are customized to the combine and the crop for peak performance. Innovative bar-and-grate style modular and one-piece MAD Concaves are built to last with high-quality abrasion-resistant (AR-200) steel, which allows for more extended wear and precision sharpness. Their easy-to-change design will enable you to customize your combine to the crop with different precision grate spacings. From alfalfa to chickpeas, MAD Concaves removes the hassle of changing concaves so you feel comfortable switching them out to get the best crop results during harvest.


We define success as helping you achieve the highest levels of yield and quality possible while increasing your efficiency and profitability through our innovative concaves.


The numbers .225, .300, .375, .437 represent the measurement of the gap between the bar; the gap being .225 of an inch.

For more information on the right configuration for your combine and crop, scroll down to view our John Deere, New Holland, and CASE IH configuration guides.

Bushel Plus MAD Concaves .225 concave for front position, wheat, flax, canary seed

.225 Concave

  • Front position
  • Reduce dockage
  • Hard thresh crops
  • Wheat, flax, canary seed
Bushel Plus MAD Concaves .300 concave for front position, large easy-thresh cereals

.300 Concave

  • Front position
  • Allows more seed out of concave reducing rotor loss
  • Large easy thresh cereals
Bushel Plus MAD Concaves .375 concave for all crops

.375 Concave

  • Mostly used in the second position but used in front position for large cereal crops that need some threshing
  • All crops
Bushel Plus MAD Concaves .435 concave

.435 Concave

  • First and second position
  • Ideal for very easy thresh crops like hemp
  • Very large seed crops, chickpeas, faba beans
Bushel Plus MAD Concaves Finger Grate Concave

Finger Grate Concave

  • Front position
  • New design for shatter resistant canola
  • Minimal threshing
  • Increased separation
  • Canola, peas, barley, oats, sunflower
Bushel Plus MAD Concave Slotted Concave

Slotted Concave

  • Front position
  • No threshing, full separation
  • No cracking
  • Edible beans, canola, sunflower
Bushel Plus MAD Concaves Alfalfa Concave Special Design

Alfalfa Concave

  • Both positions
  • Specially designed
Bushel Plus MAD Concaves Round Bar Concave for both positions, full separation

Round Bar Concave

  • Both positions
  • Full separation

NEW! The O-Grate for Corn, Soybeans, and Milo

  • MAD Concaves John Deere STS/S Series O-Grates
  • MAD Concaves Case IH O-Grate
  • MAD Concaves X-9 O-Grate


The new split frame MAD Concaves with modular inserts, for John Deere and New Holland, were developed to be lighter (68 lbs) and easier to handle and install into the combine.  Once the frame is installed it is never removed, and the modular concaves (30lbs) are easy to insert and quick to swap out in mere minutes with two bolts per insert.  With this design, you’ll optimize your yield and save on people power and recalibration time.

Bushel Plus MAD Concaves New Holland Split Frame

New Holland split frame concave with interchangeable modular inserts. Learn more.

Bushel Plus MAD Concaves S Series John Deere Split Frame

S & STS Series John Deere split frame concave with interchangeable modular inserts. Lean more.


Crop-tested and verified durable X9 concaves to get the results you’ve been looking for.


Bushel Plus MAD Concaves .225 John Deere X9 Concave

.225 X9 Concave

Bushel Plus MAD Concaves .435 John Deere X9 Concave

.435 X9 Concave


View our MAD Concaves configuration guides to learn more about what concaves you need for your crop and combine. Already have MAD Concaves? View our suggested combine settings guides.


 Amazing on All Crops Hard to Thrash!

“We have been using them for years. The latest version have no wires, flat plates with slots. They are amazing in all crops hard to thrash. We combine red clover, alfalfa and flax with no blanks, the wheat is so clean this year it looks like it has been cleaned. It is interesting to note that they have built a half set and hangers that are easy to change for a JD as well! I can change the four concave in ours in 10 mins total. You will be happy with the grain saving!”

Staff – Great to Deal with and Provided Ample Information and Advice

“We are very happy with our MAD Concaves. Keeping the frames in the combine makes changing concaves between crops a one person job. You can mix and match what grates you’d like to use depending on the conditions, making them very versatile.

We were able to open up the clearance and increase capacity, while either improving or keeping the sample consistent. We saw fewer whitecaps in wheat along with less cracking. Capacity in canola also increased, and we were also able to greatly reduce un-thrashed bols in flax, even under less than ideal conditions.

We were worried we might miss filler plates. But, there was no looking back. Staff was great to deal with and provided ample information and advice. We’re very happy with our investment, thank you!”

Stronger. Easier to Work With. 

“Think diesel tuner or 6” lift for your diesel truck. They are beefier. Stronger. Easier to work with. In addition, the company has a real knack for customer service. They may be slightly rough around the edges but they know their stuff. And they appreciate their customers. We bought a set of concaves for one of our CR combines and it does a better job of threshing and cleaning the grain than the stock concaves. When we bought it though, they provided very specific combine settings that were quite different than the settings we had been using for years. And it worked. Low throw over. Cleaner sample.”

Changeable Inserts is a Fantastic Idea.

“Bought 6 of these this year. Was able to pick up .5-.7 mph in canola due to reduced losses, and the changeable inserts is a fantastic idea.”


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