Features:Fixed drill hole design. There are 9 kinds of fixed holes, which are suitable for different bits according to the situation. Parallel line drawing function. Parallel lines draw multiple rows of holes. You can put on a suitable hole for placement in the row. Goniometer.3D Angle Ruler with Angle Scale can help you find a specific angle and mark it on the wood. Dovetail model. The 3D angle ruler has two swallowtail models, which can quickly build a standard swallowtail shape on the wood. Scope of application: 3D angle ruler is widely used in furniture making, home improvement, woodworking, professional use, etc. Specifications:Type: 3D Angle RulerMaterial: PlasticColor: BlackMeasuring Range: 0-150mm/5.91"Size: 21*7.2*6cm/8.27*2.83*2.36"Notes:Due to the different monitor and light effect, the actual color of the item might be slightly different from the color showed on the pictures. Please allow 1-3mm measuring deviation due to manual measurement. 1 X Angle Ruler