Laser print or photocopy your circuit design onto this specially-coated paper, iron it onto a blank PC board and etch it as you normally would. In just three minutes you will have quickly and easily created a custom PCB - perfect for prototyping and short production runs! The Toner Transfer System (TTS) features specially treated, letter-size, lightweight paper that can run through any laser printer or photocopier. The printed image on the paper is simply ironed onto a blank copper board, placed in a tray of water to remove the paper and then into the etchant.