Perfect stackable paint cones. 

Now there is no need to make sure you get the right side down to maintain a uniform height for your painting needs. These are perfect regular tetrahedrons, which means that no matter which side is down, the height is always the same. 

These cones are super strong as well, so you don't need to use a lot of them to support your heavy work. Go ahead, feel free to lay your heavy pieces down, these will take the weight. 

And when you're done, just stack them up any way you want. There is no wrong way. These cones are the exact same size and shape in every direction, so you dont have to spend a lot of time arranging them so they stack right. Just drop any side down on top of the next one, it'll fit just like it was made for that. Because it was.