These vials are 10 mL and filled with as much broken uranium glass bits as I can fit in them! The vials are secured with a cork and superglue, so don't get them very wet. They fluoresce under blacklight and will look poppin' at the club. If you just want the bits as an oddity for your collection that's always cool too. These necklaces are incredibly unisex and make great gifts. Handmade with love by myself <3