... 20mm/ Adjustable ABOUT US AWE BRING YOU THE BEST MOODS!!BWe're one of the Top Mood & UV & Glowing Jewelry Manufacturers ... above C. High qualityD. CustomizedOCCASIONSAnniversary, Promotional Gift, Party, Wedding, Concert, Kids, Fashion Accessories, etc.MOQ50-100 Dozens ( 12 pcs / dozen)SAMPLESA ... 30 days, depends on actual destination.SLOGANWE BRING YOU THE BEST MOODS!! Fashionable Glow in the Dark Ring