Smith NL402 Backpack Sprayer Review

Smith NL402 Backpack Sprayer for Contractors and Industrial

The Smith NL402 No-Leak Industrial and Contractor Backpack Sprayer is another terrific sprayer in the high-end Smith Performance series of backpack sprayers. This model is specially made to handle acetone, xylene, bond breakers, curing compounds and more. It features the same high-quality construction as it's brothers in this line.

smith nl402 backpack sprayer

Previously we've looked at the Smith Performance Series NL401 which is designed for cleaning and restoration as well as the Smith Performance Series NL403 for Pest Control.


Let's be clear when you spend your hard-earned money on tools like the Smith NL402 you are expecting them to be high-performance, low hassle and long-lasting. 

Sometimes less hassle becomes even more important than performance. If you’ve been around backpack sprayers as much as we have you now the hassle can start right when you open the box. Assembly or wrong assembly for that matter can indeed cause many problems down the road.

Not being able to properly attach or tighten attachments like the wand on your sprayer can inevitably cause leaks that will hinder your backpack sprayer's performance as well as your patience.

If product assembly is not your strong suit, we have some good news. The Smith Performance Sprayers, Smith NL402 4-Gallon No Leak Backpack Sprayer is a sprayer that comes with minimal assembly requirements and is coincidentally the sprayer we are going to be reviewing today!

At first glance it looks very similar to other Smith Performance models, the only stand out difference is that this model has brass finishes in the wand, the pump, and nozzles. Interesting those of you who had been complaining about the low-quality plastic parts that many sprayers come with.

The Smith NL402 4-Gallon No Leak Backpack Sprayer comes with a 4-gallon tank like many of its predecessors. As part of the no leak line, the tank can be taken apart without the use of tools quickly and easily. Helping you adjust any minor flaw on the fly so you may continue spraying.

A stand out feature is the built-in agitator that can handle liquids, powders, and water-soluble solutions. The agitator keeps all of them mixed, in a solution, and is always ready to spray.

The Smith NL402 No-Leak Contractor and Industrial Backpack Sprayer can handle water-based cleaners, sealers, release agents and curing compounds. It works thanks to a diaphragm pump system that can pump chemicals with 65% more pressure than many leading brand pumps. Providing a power of up to 150 psi that allows the user to spray up to 30 feet in distance.

The brass wand includes a shut-off feature and a 5 psi check valve to prevent liquid from dripping out after shutoff is released. The reality is that the Smith NL402 backpack sprayer is competitive performance wise, and it is better made than most out there.

Smith NL402 Features

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    4 Gal. no leak backpack sprayer
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    Internal piston pump design eliminates leaks
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    18 in. Brass Wand and Shut Off
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    Viton Seals and Gaskets
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    Padded Ballistic Nylon Harness with Adjustable Chest Clip and Lumbar Support
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    Large Tank Opening with Filtration Basket Keeps Large Debris
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    Pump Handle and Wand Storage
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    50 in. chemically resistant poly hose
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    Smith NL402 features a Stainless steel tank frame for ultimate durability
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    Multiple nozzles included for ultimate versatility: brass adjustable and 2 flat fan nozzles
Smith NL402 backpack sprayer

The Smith NL402 features multiple nozzles including brass adjustable, and 2 flat fan nozzles

What are people saying?

People online were really pleased with the Smith NL402 Industrial and Contractor Backpack sprayer almost all across the board. The problems that people found where mainly due to the heavy weight of this sprayer. That is typically a problem for people that are looking to use this sprayer exclusive for domestic uses. When in reality this sprayer can withstand the tough go of industrial grade projects.

What we liked

We liked the overall performance of the Smith NL402 No-Leak Backpack Sprayer. It really works as advertised as we have no complaints there. It does reach the 150 psi and 30 feet distance that we were to expect. The padded straps and lumbar support from the harness make it easier to carry around. The brass wand and pump make it a lot more durable. Also, the fact that we did not have to do a lot of product assembly was also a big plus. The 4 nozzle options each worked very well on the Smith NL402 contractor backpack sprayer.

What we didn't like

We couldn't find much to not like about the Smith NL402 backpack sprayer. It is very well suited as an industrial grade backpack sprayer for water-based cleaners, sealers, release agents and curing compounds. If you have other requirements, this backpack sprayer is not for you! The Field King 190350 Backpack Sprayer is an excellent option if you're looking for a general purpose backpack sprayer.


I give it 4 stars!

The Smith NL402 Backpack Sprayer the perfect tool for contractors or heavy industrial work. If you need to spray bond breakers, curing compounds, xylene, acetone and more, buy this right now because you won't find anything better.

If your requirements don't fit into those specialties, check this guide for the best backpack sprayer.

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