Vintage 60s/70s Bausch & Lomb Ambermatic Yellow Sunglasses - 58mm, etched lenses

pre-Ray-Ban, older pair of B&L Ambermatic sunglasses from the 60s-70s.  Rectangular aviator frames are VERY similar to the RB Caravan style.  Lens are etched BL.  Made in the US. Marked "B&L 58-16 U.S.A." just above the bridge. Condition:  Slight tarnishing on top of frames, minor wear at earpieces.  Both photographed, from normal wear / age.  No major scratches on lens, they're clear. GOOD VINTAGE condition, vintage items sold as-is. Comes with a brown RB branded case. SUPER RARE! These sell on ebay for $400USD+.