Nissen Temperature Sticks are an easy, economical way to determine surface temperatures. The Temperature Sticks are 5" long and protected by an adjustable aluminum holder. They are guaranteed accurate to within +/- 1% of their temperature rating. The sticks have many applications and are widely used in the welding and heat treating industries. The sticks may be used either by making a mark on the surface and heating the material until the mark melts or the material may be heated and the surface stroked with the sticks until they leave a liquid smear. The marks are easily removed with water, if they have not become charred. If the marks have become charred, it may be necessary to use abrasives to remove the marks.