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  • A red and white Milwaukee M18™ SWITCH TANK™ 4-Gallon Backpack Water Supply, featuring a coiled hose and blue handle on top. The brand logo is displayed on the front.
  • A construction worker operates a Milwaukee power cutter connected to a Milwaukee interchangeable tank system. The text above states, "No manual pumping. Interchangeable tanks. Up to 40 tanks per charge." The worker wears a high-visibility vest, helmet, and gloves. The setting is an outdoor worksite.
  • This image displays a Milwaukee backpack sprayer with highlighted features like high visibility markings, an adjustable padded harness, and a 10-foot hose with quick connect. It includes easy access latches and a protected battery compartment. An optimized tank design and a 5-mode pressure adjustment knob are also indicated.
  • The image displays a kit that includes an M18 Power Base with Switch Tank, a 4-gallon water supply tank assembly with Switch Tank, an M18 REDLITHIUM XC3.0 battery, and an M18 & M12 multi-voltage charger.
  • The image shows a Milwaukee M18 lithium battery next to a water tank with a hose, illustrating that one battery charge can power up to 40 tanks on setting 5. The text "WORK DONE" is at the top in bold red, and the main text reads, "UP TO 40 TANKS PER CHARGE ON SETTING 5."
  • The image shows Milwaukee's switch tank design with interchangeable tanks. A powered base unit at the bottom is connected to three tanks above it. The text highlights "INTERCHANGEABLE TANKS" and "MULTIPLE TANKS, SINGLE POWERED BASE."
  • The image displays two Milwaukee products with a red header reading "TANK COMPATIBILITY." The first item is the 3019-20 M18 powered base. The second item is the 49-16-19WS tank assembly. Text below confirms compatibility between the base and tank assemblies 49-16-19PS and 49-16-19WS.
  • The image shows a table with flow rates corresponding to five modes; Mode 1: 0.13 GPM, Mode 2: 0.30 GPM, Mode 3: 0.52 GPM, Mode 4: 0.77 GPM, and Mode 5: 1.26 GPM. The title above reads, "Instant, Constant, Adjustable Pressure."
  • This image features a Milwaukee backpack dust extractor next to icons of a saw and a drill, indicating use for dust management during concrete cutting or coring. Text above reads, "CONCRETE DUST MANAGEMENT," and below indicates the product is "OSHA Table 1 Compliant When Concrete Cutting and Coring."
  • A construction worker wearing safety gear operates a Milwaukee MX Fuel cut-off saw with a Rapid Stop feature, attached to a cut-off saw cart. The worksite features metal rods and stacked materials, emphasizing construction activity. Text at the bottom lists compatibility details for saw and cart kits.
  • The image shows a black droplet icon with ripples underneath. The text above reads "FOR USE WITH" in white on a red background, and below the droplet, it says "CLEAN WATER ONLY" in black and red.
  • A person wearing a white hard hat and gloves carries the M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™. The sprayer, red and white with tubing, is worn on their back as they walk in an industrial area.
  • This image features a 10-foot water supply hose assembly with a red and black connector. The text "AVAILABLE ACCESSORIES" is displayed in white on a red background at the top, and product details are below the image.
  • M18™ SWITCH TANK™ 4-Gallon Backpack Sprayer Kit Warranty
  • M18 FUEL™ 20 Dual Battery Chainsaw
  • A red and white Milwaukee M18™ SWITCH TANK™ 4-Gallon Backpack Water Supply, featuring a coiled hose and blue handle on top. The brand logo is displayed on the front.
  • A construction worker operates a Milwaukee power cutter connected to a Milwaukee interchangeable tank system. The text above states, "No manual pumping. Interchangeable tanks. Up to 40 tanks per charge." The worker wears a high-visibility vest, helmet, and gloves. The setting is an outdoor worksite.
  • This image displays a Milwaukee backpack sprayer with highlighted features like high visibility markings, an adjustable padded harness, and a 10-foot hose with quick connect. It includes easy access latches and a protected battery compartment. An optimized tank design and a 5-mode pressure adjustment knob are also indicated.
  • The image displays a kit that includes an M18 Power Base with Switch Tank, a 4-gallon water supply tank assembly with Switch Tank, an M18 REDLITHIUM XC3.0 battery, and an M18 & M12 multi-voltage charger.
  • The image shows a Milwaukee M18 lithium battery next to a water tank with a hose, illustrating that one battery charge can power up to 40 tanks on setting 5. The text "WORK DONE" is at the top in bold red, and the main text reads, "UP TO 40 TANKS PER CHARGE ON SETTING 5."
  • The image shows Milwaukee's switch tank design with interchangeable tanks. A powered base unit at the bottom is connected to three tanks above it. The text highlights "INTERCHANGEABLE TANKS" and "MULTIPLE TANKS, SINGLE POWERED BASE."
  • The image displays two Milwaukee products with a red header reading "TANK COMPATIBILITY." The first item is the 3019-20 M18 powered base. The second item is the 49-16-19WS tank assembly. Text below confirms compatibility between the base and tank assemblies 49-16-19PS and 49-16-19WS.
  • The image shows a table with flow rates corresponding to five modes; Mode 1: 0.13 GPM, Mode 2: 0.30 GPM, Mode 3: 0.52 GPM, Mode 4: 0.77 GPM, and Mode 5: 1.26 GPM. The title above reads, "Instant, Constant, Adjustable Pressure."
  • This image features a Milwaukee backpack dust extractor next to icons of a saw and a drill, indicating use for dust management during concrete cutting or coring. Text above reads, "CONCRETE DUST MANAGEMENT," and below indicates the product is "OSHA Table 1 Compliant When Concrete Cutting and Coring."
  • A construction worker wearing safety gear operates a Milwaukee MX Fuel cut-off saw with a Rapid Stop feature, attached to a cut-off saw cart. The worksite features metal rods and stacked materials, emphasizing construction activity. Text at the bottom lists compatibility details for saw and cart kits.
  • The image shows a black droplet icon with ripples underneath. The text above reads "FOR USE WITH" in white on a red background, and below the droplet, it says "CLEAN WATER ONLY" in black and red.
  • A person wearing a white hard hat and gloves carries the M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™. The sprayer, red and white with tubing, is worn on their back as they walk in an industrial area.
  • This image features a 10-foot water supply hose assembly with a red and black connector. The text "AVAILABLE ACCESSORIES" is displayed in white on a red background at the top, and product details are below the image.
  • M18™ SWITCH TANK™ 4-Gallon Backpack Sprayer Kit Warranty
  • M18 FUEL™ 20 Dual Battery Chainsaw
3019-21WS

M18 4-Gallon Water Supply Kit w/ SWITCH TANK™

Our M18™4-Gallon Water Supply Kit w/ SWITCH TANK™ offers an easy-to-use interchangeable tank design with no manual pumping. Designed to meet your water supply needs for concrete cutting and coring, the battery-powered water supply delivers instant, constant, and adjustable pressure up to 60 PSI. The 5-mode pressure regulator adjustment knob adjusts the pressure between 20 – 60 PSI for ultimate control. The M18™ REDLITHIUM™ XC3.0 Battery (included) provides you with up to 40 tanks of water delivery per charge. The 4-gallon water supply tank features a dual diaphragm pump for increased durability and longer pump life. The tank also has a wide mouth opening for easier pouring and a strainer that filters debris from getting into the tank. The backpack frame includes a premium adjustable harness and a handle, providing convenient transportation and storage. The 4-Gallon Water Supply is made up of two components – the M18™ Powered Base w/ SWITCH TANK™ and the 4-Gallon Water Supply Tank Assembly w/ SWITCH TANK™ (49-16-19WS). The Powered Base includes the motor, battery compartment, and REDLINK™ electronics, while the interchangeable Tank Assembly includes the pump, 10ft hose, and quick-connect coupler. The isolated pump, hose, and tank allows you to add on tank additional tank assemblies for different applications. The M18 Powered Base is compatible with the 4-Gallon Sprayer Tank Assembly w/ SWITCH TANK™ (49-16-19PS). The M18™ 4-Gallon Water Supply Kit w/ SWITCH TANK™ is part of the M18™ system, which is fully compatible with over 275 tools.

Includes

A red and white Milwaukee M18™ SWITCH TANK™ 4-Gallon Backpack Water Supply, featuring a coiled hose and blue handle on top. The brand logo is displayed on the front.

M18 4-Gallon Water Supply Kit w/ SWITCH TANK™

Key FeaturesSpecificationsReviews
Interchangeable Tanks, No Manual Pumping
Instant, Constant and Adjustable Pressure for Ultimate Control
Run-time: Up to 40 tanks per charge with M18™ REDLITHIUM™ XC3.0 Battery
Adjustable Premium Harness and handle for convenient transport and storage
Add-On, Replace and Interchange Water Supply Tanks w/ SWITCH TANK™
OSHA Table 1 Compliant when Concrete Cutting and Coring
Up to 60 PSI
Wide Mouth Opening for Easier Pouring
Strainer to Filter Debris
Compatible with Pesticide Sprayer Tank Assemblies w/ SWITCH TANK™

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Download Operator’s Manual
Download Service Parts List

Product Specifications

Power Source
Cordless
Motor Type
Brushed
Material Composition
Plastic|Molded Plastic|High Density Polyethylene|PVC
Length
10.5 in
Weight
18.9 lb
Height
22.5 in
Width
15 in
 
 

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