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Fast 2K Fence Post Mix and Concrete Alternative and Replacement for Fence Post and Mail Post Installs. 32.8 oz Bag of Expanding Composite Footing Compound

  • Based on 1,982 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Saturday, Apr 12
Order within 3 hours and 56 minutes
Available payment plans shown during checkout

Size: 1 Pack


Style: Fence Post Mix


Features

  • SAVE YOUR BACK: Quick, lightweight patent pending technology replaces 80-100lbs of concrete with a lightweight bag that does not require messy mixing with water that requires cleanup & preparation for filling post holes
  • FAST & SECURE: Ready to build in 15 minutes, and mixes in seconds in place and in the bag. All that you need in a compact and lightweight 32.8 oz bag that mixes into a waterproof protection for your fence posts.
  • PRO TECHNOLOGY: It's the same technology used to set utility poles by the professionals. Now you can quickly and securely set your fence posts and mail posts with a minimum of fuss & mess securely.
  • EXPANDING COMPOSITE TECHNOLOGY: Fast 2K Fence Post Backfill uses an expanding composite technology which is stronger than traditional concrete. Designed to adhere to wood, Vinyl and metal posts.
  • HYDROPHOBIC TO PREVENT ROT: Unlike concrete which absorbs water which can damage metal and wood, the Fast 2K product is waterproof and hydrophobic which prevents water from getting into your posts, reducing rot, rust, deterioration and other water-related damage.

Material: Adhesive, Sealant


Brand: H.B. Fuller


Item dimensions L x W x H: 1.5 x 8.5 x 7.5 inches


Color: No Color


Shape: Rectangular Prism


Item Diameter: ‎3.05 Centimeters


Item Form: ‎Foam


Item Weight: ‎2.2 Pounds


UPC: ‎713976908484 669602000322


Number of Items: ‎1


Global Trade Identification Number: ‎22


Manufacturer: ‎H.B. Fuller


Part Number: ‎254-20-S


Item Weight: ‎2.2 pounds


Item model number: ‎254-20-S


Is Discontinued By Manufacturer: ‎No


Size: ‎1 Pack


Style: ‎Fence Post Mix


Finish: ‎Vinyl, Metal


Item Package Quantity: ‎1


Cutting Diameter: ‎3.05 Centimeters


Measurement System: ‎Metric


Included Components: ‎Multitool Accessory


Batteries Included?: ‎No


Batteries Required?: ‎No


Warranty Description: ‎Warranty


Date First Available: June 25, 2014


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Apr 12

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

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View our full returns policy here.

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Top Amazon Reviews


  • This stuff is great
Size: 1 Pack Style: Fence Post Mix
Very easy to use and sets quickly. Rock solid, works well and fast.
Reviewed in the United States on January 22, 2025 by Steve McAndrews

  • Great product
Size: 2- 1L bags Style: Deck Post Mix
Love this product way better then mixing concrete. Has work for ever job I have used it for.
Reviewed in the United States on February 18, 2025 by radman641

  • This stuff is great. I'm giving it 4 stars because it's way ...
Size: 1 Pack Style: Fence Post Mix
This stuff is great. I'm giving it 4 stars because it's way too daggum expensive. I remember when it was $11 a bag and I thought that was too pricey. I used it to put up an 8'ft vinyl privavy fence 7 years ago. It has held up very well even with strong winds. It was pricey, but fast 2K allowed me to put that fence up by myself quickly without straining my back with heavy bags of concrete. I love the fact that it was very forgiving. I put one post in the wrong place; iit was so easy to dig it up. TIPS:: 1. When I dug my holes, instead of making the sides uniform I dug deep notches in the sides of the hole. This way the foam could go into the notches and that helped prevent any kind of movement later on. 2. When installing fence post, make yourself a jig or some type of stand to hold your post up right until you pour the fast 2K in the hole Have your post leveler already attached to the post. 3. Make sure you pour some mixture all around post.Be prepared to just hold it in place so that you only have to make quick mInor adjustments to level it. Stay calm and stay still for like 9 to 10 seconds. DO NOT MOVE THE POST ONCE THE FOAM STARTS RISING. ... show more
Reviewed in the United States on February 25, 2018 by ValleyBoy

  • Surprisingly strong
Size: 1 Pack Style: Fence Post Mix
Very easy to use. Very strong hold. I was surprised. Would purchase again. I used this for a post box post on the end of my property. It's held up better than the concrete that was originally there.
Reviewed in the United States on January 26, 2025 by Tulv

  • Great!
Size: 1 Pack Style: Fence Post Mix
Don’t get nervous thinking you didn’t purchase enough as you are pouring it into the hole. It will foam up and if overflows or looks ugly, a simple aerated knife cuts the access away. Brilliant product, quick setting…a little pricey though.
Reviewed in the United States on January 14, 2025 by customer bob

  • Was quite hopeful I found something good, took pictures and ended up giving up and buying regular old cement...
Size: 1 Pack Style: Fence Post Mix
UPDATE 1-10-15 Items were sent back (Amazon was superb, they provided a free shipping label to return the items and refunded the cost the day after the package was given to UPS). UPDATE 1-15-15 Amazon marked the items as 'received' and the credit still shows, major kudos to Amazon. Lousy is what this stuff was. I was excited and thought maybe their claim "Same advanced technology used to set utility poles for almost 15 years" might be a good indication but I can say categorically that claim is total non-sense. No way a utility company would ever use this, They might have TRIED it 15 years ago on one pole... So the details! (and I will upload pictures, I was VERY disappointed, so much so that I should have returned the empty containers to Amazon for a refund, but it is not Amazon's problem the products is lousy)... I had two posts I was putting up. These are to be posts to hold Just a hand railing, so they are not 'fence' posts, but a 6 foot fence post, holding a fence panel in the wind, (almost like a sail)? No way, this is an epic failure for that application. If you are 'effectively' OK with backfilling your post in with the equivalent of expanding spray foam, then this is your answer (not a good use, that is a pun)... So here is what I did exactly (pictures prove it!). I ordered 2 ($40) of the "Fast 2k Fence Post Backfill - 26 fl oz" packages from Amazon (after watching a video online and seeing someone use it). I read the instructions CAREFULLY (many times) and as you can see (from me wrapping my hand made posts in plastic wrap) I was concerned the blue foam might get on them and stick to them (I also put a bit of plastic wrap on walkway). The posts are regular 4x4 pressure treated that I have applied strips to, cut at an angle, and sanded and painted everything to end up with the posts you see. ONLY from ground level up is the entire design, below grade is regular 'fence post'... I also made a temporary bracket to hold adjustment to get the exact distance I wanted from both the stairs and edge of the walkway. I was thrilled at the idea of something 'encapsulating' the posts I had hand made (and therefore the posts lasting longer not dealing with groundwater rotting them out from below). Then wanting the posts in an exact spot I made up the temporary wooden alignment guide. Now comes the fun, after reading the instruction many times and being scared of the stuff, I CAREFULLY followed the directions. It was a 50+ degree day and I made sure the product was kept inside at the right temperature till I opened the bag. As you can see in my1st photo (that shows the post and the blue foam in the hole only) it did rise while it expanded but it never came up very far. I waited for over 30 minutes and it only 'rose' about 10" I then realized the hole might need a bit more so I prepped bag two and poured that on top (as directed). It too rose but not much (maybe 6 more inches) and you can see what that looked like in the photo that shows the step and foam and walkway edge. At this point I was out of foam and thought 'where will I get more, how much will it take" a guesstimate indicates this hole would have taken 4 bags and the other hole would have taken about 3 more. All said 7 bags at $20 a bag? How is $140 a good deal? NOW the 'epic failure' of this product. AFTER I carefully did not touch the post (It was very well supported) over and hour AFTER the second bag was poured and the surface of the foam was firm (not tacky) I tested the post. It moved a little bit and did not feel solid. I know the hole was not even half way filled so if it were totally filled with the Fast 2k stuff, maybe it would be OK. BUT if it were half filled with regular old cement that had cured there is no question the post would have been ROCK SOLID. I was bummed, I was not sure if I should 'chip' this foam 'junk' out (at this point I was very disappointed and the honeymoon was over) or what. I did not want to use cement then later find I should have removed the foam nonsense. I was NOT looking forward to trying to remove the post and then remove the foam and decided I would use REGULAR $4 a bag cement from the local home center. I went to the home center. bought 6 (50 pound) bags of quick crete and brought them home. I used a couple of bags and topped of the post that I had started using the 2k foam in, then on the other post I used only concrete. I ended up using about 5 bags total for a whopping $20. Had I used concrete from the start I would have used all 6 bags ($24). so $24 for a rock solid backfilled post or $140 for a post I would forever be worried about it getting 'wobbly'? I will NEVER use or recommend the use of this terrible product. I considered calling them and asking for help, but what can they do, it is a lousy solution for this application. I guess if it were a low fence post (that was in the middle of a run) and NOT under a lot of duress (say a short picket fence) MAYBE it might be OK, but a solid stockade fence, a corner post, an end post, or a gate post? absolutely a terrible idea! Don't get me wrong, Expanding foam is a great product and has MANY great uses but this is NOT a good application for it at all. ... show more
Reviewed in the United States on January 5, 2015 by E. Howland

  • KICKS OFF FAST
Size: 1 Pack Style: Fence Post Mix
EXCELLENT PRODUCT, BUT BE AWARE THAT IT KICKS OFF IN JUST A FEW MINUTES.
Reviewed in the United States on February 18, 2025 by Mangologist

  • Nice when you only need 1 bag of concrete
Size: 1 Pack Style: Fence Post Mix
Works great for small projects
Reviewed in the United States on March 4, 2025 by BRANDEE

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