Quality Materials: Our Angle Measuring Instrument Is Made Of Stainless Steel, Which Is Wear-Resistant, Corrosion-Resistant, Safe And Non-Toxic, Not Easy To Break And Deform, And Durable. 2-In-1 Design :The Two-In-One Stainless Steel Square Ruler Can Not Only Accurately Measure The Angle In The Range Of 0-180, But Also Measure The Length Of 0-100Mm Conveniently And Quickly. Easy To Use: These Stainless Steel Protractors Are Easy To Use. The Adjustable Screw Design Is Super Convenient. You Can Tighten The Screw To Read The Scales Better. Precision Tool: The Angle Measuring Tool Protractor And Ruler Are Precision Laser Engraving, Readings Are Clear And Accurate, Easy To Read, Durable And Practical For Your Use. Wide Applications:The Round Head Protractor Is Suitable For Engineering, Angle Measurement, Student Drawing, Architectural Design, Carpentry, Wall Measurement. The Length, Ideal Gift For Students, Craftsmen, Architects And Designers.