 Today I'm going to show you how to make a homemade proofing box for only a fraction of what you'd pay for any pre-built box It's perfect for bread proofing or any other fermentation projects And it's actually really easy to make with only about four components. So let's get into it So like I said, there's only four components to this box and the first one is going to be this large styrofoam cooler. I Just bought this one on Amazon and of course I'll link all the items that I used in the description below So this one is 19 inches wide by 12 inches deep by 16 inches tall And this seems to be the perfect size for me and for a point of reference It'll exactly fit a standard half sheet cooling rack Now for the heating unit, you'll need one of these Which is a seedling heating mat with this I found I can get up to about 110 degrees inside this box which is plenty high for me But if you do need higher temperatures in that you can of course look for a more powerful mat Now the third item is one that will help us dial in the exact temperatures that we need and that is a temperature controller Essentially, it just has a temperature probe on one end that monitors the current temperature inside the box And then you can use this controller here to set the desired temperature And as you can see I just screwed mine into the side of the cooler for organization purposes Now the last item which is technically optional, but I'd highly recommend it is a half sheet cooling rack So you can basically just set this on top of the seedling mat so that anything you place inside the box doesn't directly touch the mat And like I said, this box is the perfect size to exactly fit one of these. So let me show you how I set it up So it's actually really simple to set up You just place the seedling mat inside the box and as you can see this seedling mat fits perfectly for this box Then you'll just want to plug in your seedling heating mat to the side of your temperature controller that says heating Then you'll just place the temperature probe into the box so that it can monitor the temperature at all times Then you just plug in the temperature controller to the wall and that's really all there is to it Like I said, I also like to place the rack in the box Just so that nothing directly touches the mat and here you can see what it looks like once everything is set up Now from here all you have to do is just set your desired temperature on the temperature controller And it'll automatically turn on and off the heating mat to maintain that specific temperature You can see right now I have mine set to 85 degrees Fahrenheit and the light is lit indicating that it's currently heating to get up to that temperature And obviously you'll need to put the lid on to lock in the heat whenever you're trying to maintain a particular temperature So that's really all there is to it. It's super easy to make and it's also highly customizable So if you need to achieve higher temperatures You can upgrade the heating mat and you can even add a humidifier and humidity controller if you're working on Fermentation projects that require that like making Koji So overall, I'd highly recommend this comes out to about a total of $95 with this configuration I have here whereas the most popular pre-made proofing backs. I've seen comes out at about $170 I've also seen temperature controllers that are cheaper than the one that I have here And I'll also link that in the description below so you could get the price down to about $80 if you go with that option