1930's era Driving/Aviator folding Sunglasses

Unbranded, folding Driving/Aviators sunglasses fitted with 'comfort cables' and amber lenses, the lenses are in excellent condition, no chips, or scratches to them. Frames are nickel plated, in very good condition, with a 'floating' central nose pad, comfort cables are plastic coated, in excellent condition, with no issues. Very similar to A/O 'D' type sunglasses/goggles. Case is in well used condition, with very little of the black crackle paint finish remaining, with a brown cotton lining, in used condition. Rare pair of 1930's 'driving/aviation' sunglasses. s/n 37