Ball Chain #3 Aluminum Connectors 50 Count Attachment for #3 Aluminum ball chains (chains sold separately) #3 size chain has a bead diameter of 3/32 inch (2.4mm), perfect size for dog tags Bulk Packed #3 ball chain is the common chain size for dog tag necklaces Made in USA by Ball Chain Manufacturing Since 1938. We are the manufacturer, not a reseller.