Here we have for sale a complete mystery air filter cage. There was a black replaceable foam filter fitted around the metal core, but that has long since disintegrated.
It is new old stock, and was wrapped in the Suzuki bag.
It is at least 30 years old, and may be 50 years old, I just don't know.
The exact measurements are :
Distance between 2 x JIS screw centres on the top is 50mm
Width of the housing is 95mm
Length 145mm
Distance between bottom fixing hole centres is 150mm
Height of the perforated metal core that the filter goes on is 85mm
The rubber gasket tis 11mm wide and 4.5mm high.
If you buy the item and tell me what bike this fits, ideally with a photo showing the fitment, I will refund 100% of the purchase price and postage.
It may be just what a restorer requires to finish a project, I have a number of these available.
The black foam filter can be easily fabricated from sheet readily available on ebay.