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Model # 91127100

Internet # 202045449

21 in. Professional Self-Propelled Gas Mower-DISCONTINUED

This item has been discontinued.
The Home Depot no longer carries this specific product.

$829.00 /each



Model # 91127100

Internet # 202045449

When you want to go Pro. This Ariens 21 in. Professional-Grade Walk-Behind Mower features posi-traction and solid steel axles combined with easy rolling ball bearing wheels so you'll have plenty of get-up-and-go on inclines. This mower is fully loaded to enhance your mowing experience.

  • Assembled dimension: 23.5 in. W x 62.5 in. D x 40.6 in. H
  • 21 in. Cutting width
  • 6 HP/179 cc Kawasaki FJ180V engine
  • 14 Gauge stamped steel deck
  • 6 Cutting positions ranging from 1.5 - 3.6 in.
  • Variable speed belt drive
  • Speeds of 0-3.75 mph
  • 3-in-1 cutting system, side discharge, mulch, bag
  • Hihg lift baldes to maximize bagging efficency
  • Includes 2 year limited commercial warranty
  • Walk Mower is delivered 100% assembled by a local dealer who will show you how to use the equipment,disclaimer Qualifying areas only

Info & Guides

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Assembled Depth (in.) 
62.5 in 
Assembled Height (in.) 
40.6 in 
Assembled Width (in.) 
23.5 in 
Blade Length (In.) 
21 in 
Rear wheel size (in.) 
Size of Yard 
1/2 - 1 Acre 
Blade Brake 
Cutting Options 
Bag/ Mulch /Side-Discharge 
Cutting Width (in.) 
Drive type 
Rear-wheel Drive 
Engine Displacement (cc) 
Bagger,Foldable handle,Rust resistant deck,Tool-free adjustments 
Fuel Type 
Fuel tank capacity (gallons) 
Engine oil 
Lawn Mower Type 
Walk Behind 
Maximum cutting height (in.) 
Minimum cutting height (in.) 
Mulching Capability 
Number of Blades 
Number of adjustable handlebar positions 
Oil capacity (oz.) 
Product Weight (lb.) 
125 lb 
Start Type 
Sloped with Obstacles 
Walk Behind Mower Type 
Self Propelled 
Warranty / Certifications
Manufacturer Warranty 
2- year Limited Commercial 


Rated 4.3 out of 5 by 30 reviewers.
Rated 5.0 out of 5.0 by Industrial Strength Mower The Ariens Pro 21 is extremely well-built (in the USA!) with a high-quality Kawasaki engine. Mulching feature works so well I never bother to use the bag. The only disadvantage is that it is so well constructed of thick gauge steel that it weighs 100 lbs! Fortunately, the self-propelled rear wheels work well and make it easier to turn than the the front-drive models of mower. I spent considerable time searching for a well-made mower and am convinced this is one of the best. September 29, 2011
Rated 3.0 out of 5.0 by Solid with peculiarities. Positives: 1) amazing construction. It's solid. 2) extremely powerful motor. 3) agile despite its size. Negatives: 1) the set speed tends to fluctuate slightly during use as the adjustment rod moves in or out. 2) the front wheel locking mechanism engages unintentionally. 3) the gas reservoir is shaped in such a way that when being filled it's empty, empty, empty, then abruptly full and spilling fuel all over. 4) adjusting the deck height is a major pain. So all my negatives are design-related issues. They should be able to do better for such an expensive mower. I still enjoy mowing and, in the end, placed more importance on dependability, durability, and power than on design. June 14, 2013
Rated 5.0 out of 5.0 by After 25+ years of mowing with 7 discarded mowers I finally have the BEST It took some research but I am happy I finally found this Ariens LM 21 S lawn mower. THE GOOD: I bought this mower 2 years ago and I'm convInced it's perfect for me. Even with imperfect grass from the drought this mower makes it look great. It's easy to start, easy to mow with and always looks good doing it. THE BAD: 3 Honda, 2 Toro, 2 Craftsman. It was always the same. I was convenced that there was no walk behind rear wheel self propelled mower that didn't have trouble after about 6 times of using. I think they were all made as a bad joke. It always started with the rear wheels locking when pulling the mower backwards. June 12, 2012
Rated 5.0 out of 5.0 by 21 years old and still running cast-iron sleeve is the key to a good mower Upgrade to the best! Buy an ariens LM 21S! The self-propelled on this mower is industry-leading it not only pulls you uphills but it stops you from rolling down hills when turned on. The other thing I like about ariens mowers is their use of quality engines most mowers on the market use aluminum cylinders which wear out very quickly the Kawasaki Engine has a cast-iron sleeve my ariens mower has a Tecumseh vector engine which also has a cast-iron sleeve. Honda mowers do not have cast-iron sleeves nor do most MTD mowers or craftsman this is a very good mower for anyone who want something that will last. The deck is very well constructed, my neighbor just throughout a Honda mower with a rusted out deck that was much newer. June 30, 2012
Rated 4.0 out of 5.0 by Great mower, but............. This mower is undoubtedly a commercial product. It is very well constructed, and has a strong engine. However it is very heavy, 120 lbs., and as such is hard to manuever without engaging the drive. It has a great cut, starts right up, and runs smooth. The only problem I've encountered is a tendancy to stall when on an incline. I hope after I research this I will find a simple solution. I got free shipping with this item, and it was trucked right to my garage, a nice plus. April 3, 2010
Rated 5.0 out of 5.0 by Great Mower I have owned the same Ariens mower since 1992. During that time all of my neighbors have gone through 3 machines (Toro). I convinced my next door neighbor to get an Ariens about 11 years ago and they are still using that. They are great for bagging but I use mine almost exclusively for mulching and it does a great job. My boys used it in a business for about 10 years mowing anywhere from 10 to 20 lawns a week. But now I just use it to mow my lawn every week. The Briggs engine still starts on the first or second pull. My parents have now bought Ariens on my recommendation and love it. It has outlasted my brother's honda. It still looks nice. The paint job is the best in class. If you want quality and endurance Ariens's is the best. July 10, 2011
Rated 4.0 out of 5.0 by Speed control not great My speed control slides slowly into hi speed and remains there while I am using the mower. I am frequently adjusting the speed to slow down the machine otherwise I am chasing the mower. I can adjust the setting by turning a bolt a quarter turn, but to get at the bolt is not easy as the cover plate is hard to reinstall. Also the connecting piece is made out of plastic and wont last. Otherwise, a terrific mower. June 15, 2013
Rated 5.0 out of 5.0 by Purchased in 1986 - LS21 S Purchased this mower when I lived in Chicago in 1986. Move to NC then to Pa, back thru IL, to California, Maryland and now Virginia. Let me say this, it still runs great, cranks on first pull, and does a super job all these years. I have had no major issues, just a tire, a primer bulb, and last week the handle bar broke in half at the engage lever. But after a call to my local dealer, I had a new handle bar in two days and back at it. I thought about a new mower, but why? This is a super mower, and it still looks great! June 20, 2012
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