BCB Protractor Mils

This is a military protractor calibrated in Mils – differing from the one in 
your school maths set which is in Degrees. On this scale, a circle is divided into 6,400 mils.
Using the military protractor, a bearing can be plotted from one 
point to another in order to determine the bearing. This 
tool has a useful thread attached to the cross hairs of the protractor, 
to assist in the determining of that bearing.
Romer scales are included for maps at:
1:25,000
1:50,000
1:100,000
The slight blue hue of the protractor in the photograph is caused by a
 protective film over the protractor – the actual tool is made from 
clear perspex.
The protractor measures 15.2 x 9.5cm.