TeNo Stainless Steel Safe Rubber Necklace- IF SOLD OUT ON SIZE YOU WANT, YOU CAN PURCHASE THE NEW RUBBER CHAIN:
https://www.teno.com/products/thin-black-rubber-chain-1-4mm?_pos=3&_sid=fde9f3fe9&_ss=r
Ultra Thin Black Rubber Necklace with a steel wire running through the inside for extra durability.
bayonet clasp - 2mm thick
rubber - 1.5mm thick
If length is sold out, you can also use new rubber chain with new style clasp:
https://www.teno.com/products/thin-black-rubber-chain-1-4mm?_pos=3&_sid=fde9f3fe9&_ss=r