For $199 you could just go to an audiologist and have a mold taken of your ear and get an exact fit made out of a material far more comfortable. I use 3D printers and can say I would definitely NOT choose that material to shove into my ear canal. Think of how your ear moves slightly when you smile, or chew, or do anything that flexes your facial muscles. ABS plastic is hard and is not going to stay formed to your ear canal when you do any of these things. However, the proper material used for custom ear molds do have a bit of "squish" that allows them to stay firmly intact. I'm not saying this 3D printed version is a horrible idea, but it most certainly is a horrible price.