I used PETG, 20% infill, and M4x8mm and M5x8mm screws to attach it. My screws have integrated washer and lock washer, but that's not required. My X-Tronic soldering iron holder is from the X-Tronic 6040-XTS solder/hot air station, though a. they've shipped different versions of this kit, and b. looks like this rack will fit the left-hand side of several of their holders, as well as some Aoyue holders. Hey left-handers: print it mirrored and attach it to the right-hand side if you have your solder on the left.