Made of stainless steel. The entire circumference of the protractor is graduated 0-90° in both directions and can be adjusted at the desired angle to the stop. Fitted with a magnifying glass for easy reading. With Vernier for reading 1/12° = 5 minutes. The sliding blades can be locked with a lock nut. Supplied with two interchangeable blades. Blade length is 150 and 300 mm.