This is a private listing for a4h: 290 patented premium 8mm antique brass plated ball and socket clasps. They are one of the strongest and sturdiest clasps i've used. They are easy to use, extremely reliable, and an unobtrusive addition to your jewelry.These clasps are the standard 8mm size, and with both parts snapped together the closed clasp measures approximately 8mm wide at the socket, 15mm in length from tip to tip, with a height of 5mm. The plating is very durable on these little workhorse babies. I personally check each one to make sure it snaps properly shelley (nybakke) pleines at the etsy store sturdygirldesigns recommends these clasps; see third photo of her "tennis anyone" bracelet. This item is made of brass.