The imperial hypotenuse put yardstick, transparent red lines, while the British 8, marginal 16 per inch, in micrometer. On one side is the metric cm, margin mm lattice. For negative control. There is the hypotenuse is crossed lines, hidden in the feet, durable. 2 "x 18" (45cm), 1.2mm thick.
All use of exclusive special process line, hidden in the feet, never wear, but also particularly fine and clear lines, high accuracy, very convenient for designers to carry, is a professional required tools.
HASHIMA X-RAY Inspecti...