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SOLO 425 4-Gallon Professional Piston Backpack Sprayer, Wide Pressure Range up to 90 psi & Southern Ag Surfactant for Herbicides Non-Ionic, 16oz, 1 Pint

  • Based on 1,491 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Thursday, Nov 28
Order within 5 hours and 56 minutes
Available payment plans shown during checkout

Style: Sprayer + Surfactant


Features

  • Product 1: Easily spray liquid disinfectants, fertilizers, herbicides, pesticides with Solo's high-performance piston pump for tree, shrub and plant protection
  • Product 1: Solos 425 backpack sprayer includes a 20-inch unbreakable wand that securely connects to a 48-inch nylon-reinforced high-pressure hose for an extended reach
  • Product 1: Four easily changeable commercial-grade spraying nozzles-Plastic Adjustable, Fan Spray, Hollow Cone, Jet Stream nozzle and is TeeJet compatible
  • Product 1: Designed with a commercial shut-off valve that securely locks in either the on or off position to minimize user fatigue, the pump handle is interchangeable for left or right-hand operation
  • Product 2: Use with most pesticides to improve results

Description

SOLO 425 4-Gallon Professional Piston Backpack Sprayer, Wide Pressure Range up to 90 psi Since its introduction to the US market in 1964, Solo's popular 425 backpack sprayer has been the standard by which all backpack sprayers are measured. High-density polyethylene tank with ultra-violet inhibitors allows for unmatched durability and ultra-violet protection. Large 4.25-Inch opening for easy filling and cleaning. Shut-off valve and wand with an overall length of 28 inches for hard-to-reach places. 4-foot high-pressure hose. With its connecting rod-activated piston pump, the 425 is capable of producing a wide pressure range of up to 90-psi, and is capable of performing virtually every spraying task. Easily and effectively handles disinfectants, fertilizers, herbicides, pesticides, and formulations for tree, shrub and plant protection and wood and concrete finishing and treatments. Solo backpacks are constructed of high density polyethylene and other chemical resistant materials. A 1-year warranty is provided. Given proper maintenance, the sprayer should last for millions of pumps and many years of use. Each Solo sprayer is equipped with an adjustable, flat spray, hollow cone and jet stream nozzle to accommodate virtually every spraying need. Padded straps with pull tabs make adjustments quick and easy. Built-in strainers, screens and filters help keep debris out of nozzles. Pressure can be regulated to 15, 30 , 45 or 60 psi by means of a built-in pressure regulating valve. Unbreakable wand prevents damage common to brass and brittle plastic wands. Viton seals, gaskets and O-rings provide excellent chemical resistance and durability. Built for comfort. Built for convenience. Built to last. SOLO sprayers are professional grade, triple test inspected and made in the USA. The SOLO 425, with a connecting rod-actuated piston pump, can produce a wide pressure range of up to 90 psi and is capable of performing virtually every spraying task. With a proven piston pump, you will be reliably equipped for applying spray liquid or insecticides in your garden. A low number of wearing parts and sturdy technology ensure a long service life and minimum maintenance. The large filling aperture for convenient filling of the tank and smooth-running pump make spraying pleasant work. The ergonomic design contours to your back for greater comfort. Southern Ag Surfactant for Herbicides Non-Ionic, 16oz, 1 Pint Surfactant for herbicides is a wetting agent with 80% non-ionic surfactant for increasing the penetration, coverage & Overall effectiveness of almost any herbicide. Surfactant for herbicides can be used with almost all herbicide sprays including Trimec, atrazine, brush Killer & 2, 4-D amine. Please Check the herbicide product label first to see if a surfactant is recommended. Reducing the surface tension of water to insure more uniform coverage and penetration of weed killers.

Brand: SOLO


Material: Polyethylene (PE)


Style: Sprayer + Surfactant


Hose Length: 48 Inches


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Nov 28

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • The pack is reasonably comfortable to wear
Style: Sprayer
I used this all last summer to spray fish and seaweed based fertilizer around my 2 acres of orchard and gardens. It works well for me. I bought a longer tube for the wand so I can reach higher in my trees. The pack is reasonably comfortable to wear, even when full because it is well balanced and the handle for the pressure pump is easy to access when walking. When spraying my trees I tend to lock the trigger in the ON position and use the pressure pump to maintain a constant pressure. I find it very easy to use. The only problems that I have had are that the soft plastic tube came loose from the main tank and the trigger sometimes doesn't work correctly when locked in the ON position for too long. The plastic tube coming loose caused my pants to get wet because the fluid started coming out through the bottom. It was an easy fix and just required adjusting the tension on the clamp holding it in place. I think it came loose partly because I had put too much pressure in the tank. I deal with the trigger problem by sometimes releasing the lock when walking around and it seems to be fine. Even with the small problems that I had I still love this unit and am glad I bought it. I would certainly buy it again if I needed a second pack. ... show more
Reviewed in the United States on April 28, 2015 by A. Holland

  • performs as expected
Style: Sprayer
Purchased this over a year ago when I was removing popcorn ceilings, I've used it many times since, No issues. The quality of build and functionality is better than I expected. This is a tool not an accessory so Don't expect it to feel like you're wearing a regular backpack. The hard plastic tank is curved to make it more comfortable and the padded straps adequately distribute the weight of 4 gallons of liquid that you'll be walking around with. I've had several tank sprayers and this one is far more convenient. I can spray the perimeter of my house with one tank in half the time. The top cap where you fill the tank started leaking on mine, I think there was an O-ring or a Gasket that fell out. Easy fix, replaced the gasket and good as new. I've left this outside in the sun for weeks and dropped it/ stepped on nozzle tip over the year that that I've had it. Durable, Quality Tool. If it leaks or has issues building pressure, get an O-ring for the top cap ... show more
Reviewed in the United States on July 3, 2021 by Chad888888

  • Ease of use
Style: Sprayer
I ended up buying this backpack Solo sprayer for ease of use with the exception of getting it on. I have to prop it up on something high enough for me to put on. I own a Solo hand held sprayer that I was getting tired of. The backpack sprayer was very simple to assemble. I think the shoulder straps are flimsy in my opinion. So I ordered a shoulder harness. Reasonable valve for your bucks. ... show more
Reviewed in the United States on April 28, 2021 by Amazon Customer

  • Not a bad sprayer, although it needs a much better spray wand
Style: Sprayer
I like this backpack sprayer because it's just easier to make up a 3 or 4 gallon load of spray and move around our hilly property with it on my back. It's much less work than carrying a 1 or 2 gallon sprayer in one hand or on one shoulder. Having the ability to fill this with 4 gallons at a time makes the job take a little less time and that's helpful too. I didn't pay attention when I ordered and I bought this piston style this time, whereas in the past we've always bought the diaphragm style. I am not sure that I perceive a real difference in use, although they look different and there are separate instructions for each in the Solo manual. This piston backpack worked fine. I am 5'8" tall and almost 70 years old and the weight and distribution were acceptable. The rod or bar that is used to pressurize the spray is at a convenient location at the side and was easy enough to pump. The spray handle itself gave me some trouble and soon became stuck in the constant-spray position because the plastic was soft and got wedged into the little groove. That isn't good, so I knocked off a star. The spray pattern is OK. I usually use fairly large drops because it seems we always have at least a little wind and I don't want the overspray going everywhere. Not a bad sprayer, although it needs a much better spray wand. ... show more
Reviewed in the United States on October 30, 2016 by Sierra Gentleheart

  • We have two now because they are great.
Style: Sprayer
I first bought one of these for weed killer as we live on 5 acres and end up with a lot of weeks in the driveway and our walks. It took 5 minutes to unbox and assemble and almost as long to fill with water and weed killer. It has a pump handle on the side to pressurize the system and you can pump as you walk and spray. I have used it exstensively since we purchased the first one and just purchased a second for anti-algae spray (we live in FL where everything turns green) so we can try to keep our RV and Lanai clean. They hold four gallons of liquid so about 32lbs full. The straps are what you might expect for the price range, but for a normal homeowner they are more than adequate. If I were purchasing this for a job I might consider different shoulder straps because these are not terribly comfortable after an hour of spraying. All in all very worth the price and they spray quite well. ... show more
Reviewed in the United States on May 9, 2021 by FL-Reviewer

  • Straps are pure garbage. Sprayer mechanism works fine.
Style: Sprayer
The straps are the cheapest and most ineffective straps I have ever had on a backpack sprayer--and I have had several good ones. The sprayer mechanism itself is fine, but if you have three gallons of herbicide on your shoulders and the straps let go, well, you know how much profanity can result. Solo used to be a sound product years ago, but the plastic "clamp on" strap fixtures at the bottom and the astoundingly cheap plastic pins at the top are something Solo should be ashamed of. I cannot believe the crap that sells for $80. If you want to buy a good sprayer, perhaps Google search RelaxPack. Costs lots more, but at least the reservoir will remain attached to you and even be semi-comfortable. I have sprayed hundreds of gallons with other backpack sprayers and I NEVER had a strap detach before. Nobody wants to dump 3 gallons of Glyphosate and 2,4-D to the ground because the straps are so poor and readily come undone. I cannot tell you how disappointed I am with this Solo sprayer. ... show more
Reviewed in the United States on April 9, 2016 by Bradley Gore

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