[Sturdy Box]: These compass sets are made of sturdy metal, stable central drive axle, stronger than plastic compasses. The sturdy metal design allows for precise and precise drawings. They can be used for a long time. [Extension Beam Design]: The extension beam is connected to a large compass to draw a large circle. You can draw a larger circle without having to do a lot of measuring and connecting dots. [Drawing Wizard] Geometry tools, perfect for math classes, sketches, architectural drawings, building designs engineering, mechanical design and construction. [The best gift]: Enough tools for teachers and students of all levels. It is also a perfect gift for kids and homeschool math students to learn painting. [Application]:This set is developed by experienced math professionals and is suitable for most levels of students, teachers, designers, artists, etc. To meet all your needs for drawing circles and measuring angles. Product size: 10 x 20 cm Product color: blue Delivery quantity: one set Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.