This is an awesome piece of history.  It is a military green color which means that it could have been used in the military but cannot be certain.  The unique outer open clip design is very functional and proprietary for the time.   It still functions well.  The clip system alone is amazing and the fact that it is still attached to the metal board makes it even better.  Overall a must have for any industrial collector.   If you are Canadian or into vintage Canadian pieces,  this is for you.   Please let me know if you have any other questions.   $15 for shipping in the lower 48 states.