This is a necklace:

• OAO brand
• 14K yellow gold
• Rope chain sparkles in the light
• Push lock with safety catch
• 16” long
• 1.5mm wide, I believe (please see photo with ruler)
• 3.63 grams
• Ships to you in a gift box.

I bought this in the 1980s from Macy’s Fine Jewelry Department.