Milwaukee 2780-20 M18 FUEL Lithium-Ion 4-1/2 in./5 in. Paddle Switch Grinder (Tool Only)

Milwaukee Model: miln2780-20
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Milwaukee 2780-20 M18 FUEL Lithium-Ion 4-1/2 in./5 in. Paddle Switch Grinder (Tool Only) Milwaukee Model: miln2780-20
price for vip customer


Product Features & specs :

M18 FUEL Lithium-Ion Paddle Switch Grinder performs like a corded grinder


World’s first cordless grinder with corded performance (battery and charger sold separately)

M18 FUEL Lithium-Ion Paddle Switch Grinder provides more run-time per charge


POWERSTATE Brushless Motor provides more run-time per charge (battery and charger sold separately)

M18 FUEL Lithium-Ion Paddle Switch Grinder has the same durability as corded grinders


Same metal housing and gearing system as legendary high performance corded grinders (battery and charger sold separately)

Milwaukee 2780-20 M18 FUEL Lithium-Ion 4-1/2 in./5 in. Paddle Switch Grinder (Tool Only)

The Milwaukee 2780-20 M18 FUEL 4-1/2 in - 5 in. Grinder with No-Lock Paddle Switch is the industry's first cordless grinder with the power to tackle heavy-duty grinding applications. This brushless grinder delivers 8500 RPM to tackle fade-free grinding, surface prep and cut-off jobs. A slim ergonomic handle and large paddle switch ensure comfort with or without gloves, and the shock absorbing handle reduces vibration. The no-lock switch is fully OSHA compliant and ensures a dropped grinder won't continue spinning. A tool-free guard helps users make quick adjustments while the 5/8 in. - 11 arbor accepts common cut-off wheels, grinding discs and wire cups. Legendary Milwaukee durability is found throughout, as this grinder uses many of the same components found in our durable corded units.
  • POWERSTATE brushless motor delivers 8500 RPM of grinding and cutting speed and the power of a corded grinder
  • Utilizes the same metal housing and gearing system as Milwaukee high performance corded grinders for ultimate durability
  • REDLINK PLUS Intelligence optimizes performance and monitors tool to prevent damage from overload conditions
  • Large no-lock paddle ensures comfort during long grinding and cutting applications and is fully OSHA compliant
  • Tool-free guard adjusts with ease
  • The world's first cordless grinder that delivers the performance of a corded grinder
  • Compatible with all M18 REDLITHIUM batteries
What’s Included:
  • M18 FUEL 4-1/2 in. - 5 in. Grinder with No-Lock Paddle Switch - 2780-20
  • (1) 5 in. Type 27 Guard
  • Flange Nuts
  • (1) Spanner Wrench
  • Battery and charger sold separately
Power Source
UL Safety
Wheel Diameter
5 in
No-Load Speed (RPM)
CSA Safety
Switch Settings
Wifi compatibility
Batteries Included
Battery Type
Case Included
Bluetooth Compatibility
Motor Type
Spindle Thread
5/8 in - 11 in
Variable Speed
Switch Type
Non-Locking Paddle
Arbor Size
5/8 in - 11 in
Charger Included
ETL Safety
Battery System
15 in.
3.27 in.
8.58 in.
5.8 lbs.
Warranty Term
5 Year

Reviews :

4.8 / 5.0
571 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Would you recommend this product?
Yes (42)
Easy To Use (39)
Powerful (37)
Ergonomic Design (32)
Value (10)
Heavy (2)
Short Run Time (if applicable) (1)
Best Uses
Frequent Use (13)
Small Projects (12)
Jobsite (11)
Home Repair (10)
Would you recommend this product?
Easy To Use
Best Uses
Frequent Use
Large Projects
Small Projects
Home Repair
Mostly Good
Great tool. Only issues are the heat it puts off after frequent use, and the fact that the handle seems a bit unruly even with my large hands.
October 22, 2020
3 months ago
Describe Yourself:
Avid Do-it-Yourselfer
Fantastic Grinder!
Plenty of power and well balanced! Great battery life too!
October 18, 2020
Originally posted at
first uses of new grinder
I used the grinder with a zip cut wheel on a project that I was working on . The grinder had enough power and did a good job.I used a 5 amp battery that almost lasted to the end of the project. The project was away from an electrical supply, so a corded tool was not an option..
October 18, 2020
Originally posted at
Great power and easy to handle
This product is used most days, battery life is great. I use it to cut duct work, rod, steel angle, concrete you name it I have used it to cut it. I like the paddle switch, it act as a safety, once you let go it is stopping and you can lock the paddle to prevent the grinder from starting if the switch get bumped.
October 17, 2020
Originally posted at
Great cutting and grinding
Grinding metal to stone. Great performance with little vibration or bucking. Lots of power ( while battery lasts). Gear head a somewhat larger and reduces cutting depth.
October 15, 2020
Originally posted at
Perfect where cords won't reach
Great under logging trucks when cords can get in the way. Does consume batteries but still able to cut out two cam tubes and prep for install of both on one battery
October 15, 2020
Originally posted at
This is awesome.
The grinder is awesome. Very easy to change out disc's. And very easy to use.
October 14, 2020
Originally posted at
Good Grinder
I’m a Heavy Duty Mechanic. I got this to replace my dewalt 20v and am pleased with my purchase, plenty of power and 5.0ah lasts a good amount of time too. Good job Milwaukee
October 12, 2020
Originally posted at
Quality Milwaukee product!!!
I use this on odds and ends for work but truly awesome grinder I would recommend
October 11, 2020
Originally posted at
Best one on market
The power is amazing for cordless especially using high output battery the functionality of it in your hands is comfortable and safety on is perfect for quick movement I love it
October 8, 2020
Originally posted at

Q & A :

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Browse 11 questions Browse 11 questions and 13 answers
Is this compatable with the HD9.0 battery?
Jimmy S on May 29, 2019
BEST ANSWER: It is compatible with any M18 Milwaukee battery. The heavier 9.0 battery could make it a "handful," affecting the balance of the grinder.
Will this work with a normal 18v battery or does it have to be the XC 4.0
Ross on Dec 23, 2014
BEST ANSWER: The grinder will work with any M18 series battery
Does this come with a wheel?
This guy on Jun 2, 2020
BEST ANSWER: No, tool only with this model.
if these are so good how come they have recondition ones already ?
A shopper on Sep 29, 2018
BEST ANSWER: Your question will be best answered by the manufacturer, who can provide you with the accurate information. The number to reach the technician directly is 1-800-729-3878 or online at
Does it come with a case or bag?
A shopper on Aug 17, 2018
BEST ANSWER: The item will not include any case or bag.
You said milwaukee has a 5 year warranty i bought my milwaukee grinder 8 months ago it stopped working can I send it to y'all warehouse and get a replacement or how will that work? thank you
chino on Sep 13, 2017
BEST ANSWER: Milwaukee warranties will need to be handled through the manufacturer directly. They can be reached at 800-729-3878. From there you will be referenced to a service center in your area
What is the warranty on this item?
waylon on Dec 10, 2015
BEST ANSWER: Milwaukee offers a 5 year warranty on this tool.
I bought this tool to use on a log home sanding large pillar logs.

Where can I find/buy the accessories to do the job? Sanding disks, backing pad, spindle, disc nut, etc??
Thanks for the help
Rod on Sep 16, 2014
BEST ANSWER: Please contact the manufacturer direct at 1-800-729-3878 for a service/parts center in your area.
where can I find the flange nut kit for the milwaukee 18volt cordless grinder?
A shopper on Apr 20, 2018