Finnish Kemira Sabre Gas Mask

A strange Finnish industrial mask made by Kemira safety, the mask is marked Sabre at the top but takes British/Swedish style WW2 filters, the mask is very advanced for what I would assume to be the 1950s, with a panoramic lens and an oral nasal cup, and a 5 point head harness with rubber straps and buckles.
The Kemira/Scott SARI respirator appears to be the modern equivalent of this mask, the Finnish M71 mask is also similar.
The mask came in a British Light-anti-gas respirators carry satchel as well.