A method of producing an L-shaped product which includes an L-shaped flat top wall, an inside wall extending and connected along an inside edge of the top wall, and an outside wall extending and connected along an outside edge of the top wall, each of the inside and outside walls being terminated by flange substantially parallel to the top wall, is disclosed. In another aspect, various retroreflection configurations are provided which optimize retroreflection of back-scattered light energy from the medium. A graph is generated linking the two or more web pages and the one or more features. A clutch is configured to permit rotation of the drive sleeve and the dose dial sleeve with respect to the housing when the dose dial sleeve and drive sleeve are coupled through the clutch.