Metric, 10 segments Material: Composite design - two top layers made of longitudinal glass fibres absorb bending forces and ensure more rigidity than wooden rules. No swelling with water contact, resistant to chemicals. Joints Play-free, wear-free and dirt-resistant joint with spring pin for constant tension. Tight 90° and 180° latching of all joints. ScaleRed/black version: Deep-embossed white scale in 1 mm increments, white embossed tens scale. Accuracy: CE conformity, EU standard accuracy class II. Metal ends which cannot be lost on the first and last segment.Scale running backwards (recto and verso) enables reading from both sides