Why can't we get an angle from two connected edges? - Basics & Interface - Blender Artists Community
Plastic Goniometer Quick Angle Protractor Clear Angle Finder Angle Ruler Can Rotate 360 Degree 7'' Arms Measuring Tool for School Office Measuring : Amazon.co.uk: DIY & Tools
KDK - Led Digital Angle Ruler Protractor Inclinometer - 300mm - 2 In 1 | Konga Online Shopping
Blender Guru - Awesome new feature! The "Ruler/Protractor" button. Allows you to click and drag anywhere to see the measurements :) Download the latest build to use it: http://builder.blender.org/download/ | Facebook
How to attachment text lable(like the text from Ruler/Protractor) to an object - Basics & Interface - Blender Artists Community
Latest features in Blender for CAD users | Rainnic in the Clouds
objects - How do I measure a distance between two points? - Blender Stack Exchange