How sad. There's nothing worse than getting a tool that doesn't work. Sure it's close, but when you're measuring an angle you need accuracy, and that's not accurate. For both 45 degree interior and exterior angles, the deviation is about 1 degree (difficult to measure without spending a lot of time). At 90 (perfectly flat and level) the outer ring is accurate, but the inner ring is offset 1 degree. It doesn't even agree with itself. If "pretty close" suits you then this might be the tool for you, but if accuracy is what you're looking for, look elsewhere.
Laser pointer Green Laser 303
31 Review
Gaming chair AeroCool Baron, upholstery: imitation leather/textile, color: steel blue
35 Review
Cullaby Contour Gauge: 10 & 5 Inch Duplications For Perfect Templates Of Curved And Odd Shapes, Plus Bonus Angle Ruler & Carpenter Pen!
23 Review
Laser level Zitrek LL1V1H
36 Review