This is a vintage Bay III light green filter.
It fits all of the 80mm f2.8 Planar and Xenotar cameras.
It is in good condition with moderate wear and works perfectly. There is a small patch of coating wear on the front of the glass but it will not affect your images. Otherwise the glass is clean and scratch free with no haze or fungus. The mount shows light wear.
The cool leather case and original box are included. There is a small amount of writing on the box but it is only cosmetic.