https://matilde.jp/view/item/000000000476?category_page_id=other
【1970s】TIFFANY&Co. Double Shackle Key Ring | VINTAGE,OTHER | MATILDE
shackle keydoubleringvintagematilde
https://www.s3i.co.uk/solid-shackle-key.php
Shackle Key | S3i Group
shackle key, stainless steel, 316 grade, shackle pin, solid
shackle keygroup