This unique design of flat flexible measuring tapes comes in two basic styles: direct reading linear tapes (LT) and direct reading diameter tapes (DT) for measuring round objects, also referred to as a Pi Tape. Simply use the tape to measure the diameter, and read off the circumference directly. Tapes are made of a vinyl impregnated polyester woven fiber 1.1” wide with easy to read graphics in both English and Metric. The case is made of fiberglass reinforced plastic with stainless steel fasteners that provides rugged outdoor use. Also available without the case and triangle loop at end, and as replacement tapes. Yellow in color, Figures for diameter tapes show diameter read, not tape length.