Thank you for viewing. This is a TWIST RING binding fastener for B5 size, 29 holes, set of 4, capable of holding 100 sheets of copy paper. I mistakenly purchased this while looking for something to bind loose-leaf paper. I opened the package once to check if it fit loose-leaf paper and tried one, but it didn't fit, so the rest are unused. I will wrap it in bubble wrap and ship it via Nekopos. Thank you very much. m(*_ _)m