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Gasoline Knapsack Mist Duster GMD-420, for Multiple Applications And Uses

The powerful and efficient 56.5cc engine provides outstanding power performance and increases fuel efficiency.
Because all relevant control elements are integrated in a single handle, the ergonomic handle allows you control your power tool easily, comfortably and reliably with one hand and provide a comfortable grip.
Easy-start recoil starter help you start the engine easily with just one or a few pulls.
Ergonomic back plate design, wider and thicker shoulder straps help the operator work more comfortably.
The 1.5-liter large-capacity fuel tank allows you to work continuously without frequent refueling.


This Back Sprayer is Powered by a 2-stroke gasoline engine of 56.5 cc.

Ideal tool to protect the crop from pest attacks, spraying insecticides, pesticides, fungicides, herbicides, etc, in field areas. These sprayers have multiple applications and are widely used in agriculture, horticulture, sericulture, plantations, forestry, gardens, etc.

Designed with a 14.0 liter chemical tank for liquids and powders, as well as an ergonomic backpack, multifunctional control handle and anti-vibration system. The back sprayer GMD-420 is equipped with a practical transport system. Its weight is evenly distributed between the shoulders and back to ensure maximum user comfort.


Package dimension 500 x 340 x 680 mm (19.7 x 23.4 x 26.8 inch)
Gross weight 12 kg (26.5 lbs)
Net weight 10.6 kg (23.4 lbs)
Application type Heavy-duty
Displacement 56.5 cc
Engine power 2.5 kw / 3.5 hp / 7500 rpm
Fuel Mixed gasoline and two-stroke air-cooled engine oil with a ratio 25:1
Fuel capacity 1.5 L
Air flow rate 1152 m3/h
Container capacity 14 L
Discharge rate 0.14~3.03 L/min


(1x) Power mist-duster

Pleated hose (with 64-76mm worm-drive clamp & 75mm spring clamp)

Spay tube A (black)

Spay tube B (black)

Air guide tube

Horizontal powder spray tube (white)

Vertical powder spray tube (white)

Lower pleated lower powder spray tube (blue)

Infusion hose (10×1.5 L=680)

Constant nozzle combination black (without spray cover)

Fuel mixing bottle

Spray cover plate A (black)

Spray cover plate B (black)

Spray cover plate C (black)

spring clamp 0.8×12.5

Spring clamp 0.8×14.5

Flat screwdriver and socket wrench 13×19 combination tool

Lengthened hex key (S=4)

Seeking high-quality accessories for your machine? Submit an inquiry now!

Please provide the model type of your machine in your inquiry, and mention the keywords like chainsaw parts, brush cutter parts, sprayer/mist duster parts, leaf blower parts, hedge trimmer parts, water pump parts, generator parts, engine parts, lawn mower parts, etc.



Q       Are you having trouble starting your gasoline sprayer?
A       To begin the start-up process, fill the fuel tank with a 50:1 fuel mix. We recommend using Craftop Brand Oil the proper fuel mix ratio. Here is a link for a correct mix of oil and gasoline. The priming bulb is located towards the bottom of the carburetor. Pump the bulb 5-7 times until fuel begins to flow through the fuel pipes. Position the choke upright on a cold start (first start – right out of the box). Set the throttle to 50%. Pull the recoil starter 3-5 times to get the engine to start. Push the choke down once you hear the engine flutter (turn over). Set the throttle to 50%. To start the engine, pull the recoil starter. Allow the engine to warm up for 1-2 minutes at low throttle.
Q       How should you rinse your gasoline backpack sprayer?
A       Fill the tank halfway with fresh water. Then, pump the handle while holding the trigger wand open to spray out everything in the tank. Pump the handle a few dozen times while keeping the trigger open.
Q       When and how often should I clean my gasoline sprayer?
A       After each usage, your sprayer should be drained and cleaned. It is normally acceptable to leave the product in the sprayer if you intend to spray again later that day or the next day. If you are not going to spray again for at least a day or two, you will need to drain the tank. You should triple-rinse your sprayer after draining the tank. This entails flushing the system three times with fresh water to remove as much chemical residue as possible.
Q       What is a gasoline sprayer?
A       It is a useful and effective device for protecting plants from diseases and pests; it is ideal for plantations, cultivated fields, gardens, and parks.



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