Jacob's ladders I sent one to my sons class, with a set of hot gloves and a big screwdriver to start the arch. When the teacher saw it he said"NOOO Wayyy" and went and got one the school had so my son could show his project. The only difference between mine and the schools was the schools had an on off switch, mine had hot gloves and directions to keep kids at a 5' distance and pull the plug if they will not stay that far away.He got an A.