DescriptionThis product is a good teaching aid, very suitable for teachers to explain angle-related knowledge to students.The sliding rocker arm can demonstrate obtuse angles, right angles, acute angles, etc., and the scale is clear.Can help students deepen their impression.Features-Material: ABS -Preservative design, made of high-quality materials, durable and practical. -The scale is clear, the method of use is simple, suitable for students and teachers. -One tool can learn about obtuse angles, right angles, acute angles and other related knowledge. -Practical gifts for students, the swing arm is easy to slide, you can use this tool to make pictures. -Fine workmanship and premium material, this product is durable and safe, as well as reasonable.