18k Yellow Gold 16" Non-Adjustable. 3.1mm. Our Charms and Coins with our Standard Bail are designed to clip around this chain. Charms and coins will slide along this chain, and will not remain stationary. If multiple charms are worn, they will fall together at the bottom of the chain. The charms on our vintage watch fob style bail do unfortunately not fit around this chain.  Made in Italy, each piece sold helps ocean-related causes.