The protractors include 1 hollow semicircle protractor and 1 semicircle protractor, which you can choose. The protractor triangle ruler also has a hollow design, which is convenient for reading the data of small patterns.
The protractors include 1 hollow semicircle protractor and 1 semicircle protractor, which you can choose. The protractor triangle ruler also has a hollow design, which is convenient for reading the data of small patterns.