Book Screw are perfect for binding thick documents because they are available in many sizes. It offers durable binding that is inexpensive and simple. It easy to use, you just need to a get holes in your document to use them.
Size : D x L (mm) , C=10mm
(5 x 5 , 5 x 8 , 5 x 9 , 5 x 12 , 5 x 20 , 5 x 30 , 5 x 40)
(Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/-1-3 mm)