The Bayer Contour test strips 200ct are very simple to use. The strips are made from plastic and coated with 1 layer of enzymes. These enzymes can Be either glucose oxidase or glucose dehydrogenase. Once a drop of blood is placed on the end of the Contour test strips, insert the strip into the glucose meter. The monitoring system will then send these electric currents, if you will, through the strip which will then enable it to read the exact sugar level in the blood tested.