Copper Naphthenate 17% (2% as Metal) Double Strength - Highest Concentration Allowed - 1 Gallon - Wood Preservative

Arrived promptly and was well packaged to prevent spillage. I wore a respirator, nitrile gloves, long sleeves, and glasses for protection. I applied two coats with a four inch brush and used half a cup to cover a 16 square foot plank, which will contact the ground. Goes on easily, absorbs well. Colors the wood green, so easy to see where you have applied. Strong odor that diminishes daily. Hoping planks last a decade.

Great stuff! Wear your PPE though, stains whatever it touches. Easy application, dries quickly, good penetration, nothing bad to say.

Purchased and used a gallon to provide secondary preventive protection to (a) a new house's 6x6 pressured treated household power pole, (b) the pressured treated plywood backer for the power box, and (c) 168 linear feet of 5/4x6x8' ground contact pressure treated deck boards (ground placement, to help stop unwanted water & dirt erosion). Product is easy to use (I used a 3" foam roller), covering all end cuts and all sides of the lumber (including the deck boards' edges). It does have a distinct odor, though, despite the plastic bottle, ziploc bag, and Amazon box (like another commenter described). The odor lessens over time (for me, it was 3 months of waiting between order and use), and I could barely smell it during application. It soaks into wood well, even "big box store, too wet, lumber". However, for those that care about looks... you are applying a copper based protection to the lumber; It will be greener. Prevention of future decay, for my uses, was the goal. We'll see how it does many years from now... when this review likely won't matter. :)

Starting with my one dislike is the price, which despite its eye watering elevation appears to be the 2022 norm for the building supplies industry. That is the major downside to this paint. Having said that I’ll be quiet and go on with the review. This is an easy to apply thin green paint which contains 2% copper, which I believe may be the best (currently not banned in most of the US) residual insect killing fungus suppressing ingredient. Its essentially similar to the green color of treated wood since somebody governmental made manufacturers stop using arsenic as wood treatment. It tends to drip, but can be brushed, rolled or used to soak wood, and lasts a long time once it is dry. It smells of naptha, but its use is outdoors only. My intended use is for treating some 6x6 wood I need to make the foundation of a shed. (The reader is warned to not look at store prices of 6x6 treated lumber if they have any sort of condition which might make them prone to fits of outrage. If anything its worse than paint prices.)

Used this on our dock at the lake to help preserve the wood from the moisture. So far, so good. It was recommended by the lumber company where we got the wood, and it seems to be working just fine! So glad we got it. It is very messy to paint on after the fact. If you can treat your wood with it before installation (I know, and extra step, right?), it will be easier to manage.

Meant to get the 19% but 17% is good too. I mix it with deck stain, diesel fuel and motor oil. Works great. No more rotten decks. I am getting too old to be building decks over and over.

Foul-smelling stuff, but what do you expect? Penetrates well. Green color when dried fades to green/brown. Don't know how long it will last, but the strength of the smell is encouraging. Wear gloves and know that splashes will be turquoise for a LONG time, if not forever.

No one can give an honest review of this unless they’re coming back 10 years after using it to mention if it works or not. I’ve used the Rustoleum version of this in the past so I was aware of the odor and thought people commenting on the odor were being over dramatic, after all, you’re buying it to protect wood, not freshen the air. I’ll say this, if the smell is any indication of how well it works it must work great. I’m surprised the post office delivered it… It was in a sealed plastic container, that was sealed in a ziplock bag, which was sealed in a cardboard box which was sealed in the Amazon shipping box and when I brought the package in and sat it on the table, before even opening the outermost box, the smell was filling the house and I had to sit the box outside. I used this to treat the entire top of a 10X20 deck we built for a hot tub, I went with this over the Rustoleum version because there’s was only .88 gallons (weird) this was a full gallon. There is also a higher percentage of the active ingredient in this, so you get more product and it’s stronger. It also smells a lot stronger than the Rustoleum so I’ll take that as it’s going to work better. I’ve seen people use the specialty deck sealers and stains and it just doesn’t last or hold up. None of those are code approved for treating structural wood that can then be buried underground so I figure this will work much better, I also wanted to keep the raw treated lumber look and this fit that bill, time will tell how well it works, so 10 years from now I’ll come back and update. The package says the smell and color will fade in time, hopefully the smell fades sooner than later because after treating the deck I can still smell it outside, strong, a quarter mile away walking up to my mailbox and the smell has permeated inside the house. Another plus, application was easy, I just poured it in a paint pan and brushed it on with a 9” brush, it soaks right in, no need to worry about brush strokes or marks. It also covers the area it claims, most things claim to cover so many feet and I end up getting about half what they claim. This says 100-300 sq feet and I got a generous 200 sq feet out of the gallon, with enough left over to 2nd coat heavy traffic areas. My only real complaints: There’s nothing on the label to indicate a before use cure time, it just says 1 hour before a 2nd coat if desired. There’s nothing on the label to indicate how long you have before rain. There’s nothing on the label to tell you optimal application temperatures. So I’m taking all that to mean none of it matters? There’s also nothing on the label to indicate if it gives UV protection or not.