Perfect for students, machinists, carpenters and woodworking hobbyists for setting bevels, measuring and transferring angles Deeply etched graduations read from 0° to 180° in forward and reverse directions and will not wear or rub off Easier to identify the precise angle Stainless steel for, strength and rust resistance Adjustable protractor arm locks into desired position with knurled thumb nut to quickly and easily identify angles, Manufacturer: SHANGYAKEJI