Vintage 1/20 14k Gold Filled Thin Double Link Chain Spring Clasp Necklace. Marked 1/20 14K GF on clasp. Will need to be cleaned, otherwise good preowned condition with appropriate wear. Please see pictures for details. I will combine shipping.

Approximately - 

18" in length when unclasped (clasp included in measurements)
0.5mm wide double links
Less than 1 gram