Specification:  Material: Aluminum Alloy.  Color: Black.  Triangular ruler part size (approx): 18 x 25 x 25cm/7.09 x 0.98 x 0.98inches(length x longest side x height).  Extension arm size (approx): 16 x 2.7 cm/6.3 x 1.06 inches (L x H).  Overall length of longest side (approximately): 31.7cm/12.4inches.  Measurement Accuracy: 0.1.  Features:  - Material: Sturdy aluminum alloy construction, durable and lightweight, easy to store in your work bag or pocket.  - The easy-to-read level tube and metal scribe on the side of the combination ruler add to the product's practicality and versatility. This square can be used as a guide for crosscutting the wood. They all work accurately at 90 or 45 degree angles.  - Foldable Ruler Rod: 6-inch foldable extension arm to meet 6-inch or 12-inch layout needs, increase the measuring distance when opened, and reduce storage space when folded. Easy to carry.  Package included:  1 x Foldable Angle Ruler