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PACKOUT Modular Storage System
3019-21PS

M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™ (Kit)

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M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™
3019-21PSM18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™ (Kit)

In The Box (4)

4-Gallon Sprayer Tank Assembly w/ SWITCH-TANK™
(1)
4-Gallon Sprayer Tank Assembly w/ SWITCH-TANK™
M18™ REDLITHIUM™ XC Extended Capacity Battery
(1)
M18™ REDLITHIUM™ XC Extended Capacity Battery
M12 and M18 Multi-Voltage Charger
(1)
M18™ & M12™ Multi-Voltage Charger
(1)
Backpack Sprayer Hose Handle and Wand Assembly

Specs

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Product Overview

Our M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™ delivers the industry's best pressure control with no manual pumping and an interchangeable tank design. Designed to meet the needs of professional landscape maintenance, the battery-powered backpack sprayer provides instant, constant, and adjustable pressure up to 140 PSI and a 24 ft vertical spray distance. The 5-mode flow rate knob adjusts the flow by 0.1 – 0.52 GPM, giving you the capability to complete a wide range of applications. Our M18™ REDLITHIUM™ XC4.0 Battery (included) provides you with up to 20 tanks of spraying per charge (on Mode 3). The 4-Gallon Sprayer Tank Assembly features a dual diaphragm pump for longer pump life and Viton® seals for increased durability against harsh chemicals. The sprayer tank has an optimized design for better weight distribution, a wide mouth opening for easier pouring, and a strainer that filters debris from getting into the tank. The backpack frame includes padded straps, lumbar support, and a hip belt, giving you added comfort during extended spraying applications. The 4-Gallon Sprayer is made up of two components – the M18™ Powered Base and the 4-gallon Sprayer Tank Assembly. The Powered Base includes the motor, battery compartment, and REDLINK™ electronics, while the interchangeable Tank Assembly includes the pump, hose, and wand. The isolated pump, hose, and wand design allows you to add on tank assemblies for different spraying applications, eliminating cross-chemical contamination. The Powered Base is also compatible with the 4-Gallon Water Supply Tank Assembly (49-16-19WS). Our M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™ is part of the M18™ system, which is fully compatible with over 300+ tools.

  • Instant, Constant and Adjustable Pressure for Ultimate Control

  • Add-on Interchangeable Tank Assembly to Eliminate Cross-Chemical Contamination

  • Run-time: Up to 20 tanks per charge with M18™ REDLITHIUM™ XC4.0 Battery on Mode 3

  • Adjustable padded harness with lumbar support and padded hip strap for added comfort

  • Optimized design for better weight distribution

  • Dual Diaphragm Pump: For Longer Pump Life

  • Critical seals: Viton® for increased durability against chemicals

  • Wide Mouth Opening for Easier Pouring

  • High visibility tank markings for easy fill management

  • Tank identification stickers for easy tank identification

  • Easy access latches for quick battery and tank swaps

  • Compatible Tank Assemblies: 4-Gallon Water Supply (49-16-19WS) & 4-Gallon Backpack Sprayer (49-16-19PS)

Product Documents

Manual / Parts List

Reviews

Product FAQ

Q:

Is There A Tank Agitator For Mixing Chemicals And Water?​

A:

The M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™ does not have an in-tank agitator

Q:

Are The Water Supply Accessories Compatible With The M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK™? ​

A:

No, water supply accessories are not compatible with pesticide sprayer tanks. Additionally, pesticide sprayer accessories are not compatible with water supply tanks.​

Q:

What Is The Difference Between The Backpack Sprayer And The Water Supply?​

A:

The M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK is designed for a variety of spraying applications with a feature set optimized for the precise application of chemical. The M18™ 4-Gallon Water Supply w/ SWITCH TANK is designed to be operated with clean water only. It’s most commonly used with concrete coring drills and cut-off saws to suppress silica dust and help users maintain OSHA Table 1 compliance in concrete coring and cutting applications. The Water Supply Kit also includes a quick-connect water nozzle that can be attached to the hose to facilitate easier water spraying. Each tank assembly is equipped with a different pump that is designed to deliver the optimal ranges of pressure/flow rate for their respective applications..​ ​ ​

Q:

What Is The Part Number For The Interchangeable Tank?​

A:

The part number for the M18™ 4-Gallon Sprayer Tank Assembly w/ SWITCH TANK™ is 49-16-19PS.​

Q:

What sprayer accessories are also compatible with the M12 1 & 2-Gallon Sprayers?​

A:

Sprayer Nozzles (49-16-2806)​ and 18” Short Sprayer Wand (49-16-2729)​. ​

Q:

How do I clean/maintain my sprayer and how often should I clean it?​

A:

Refer to the manual or the SWITCH TANK Cleaning Guide 2025 for instructions on cleaning and maintaining your M18™ 4-Gallon Backpack Sprayer w/ SWITCH TANK. It’s recommended that the sprayer is cleaned before storing and switching chemicals. Ensure the filter is clean and installed before each use for optimal performance.​

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