Give presentations, reports and other booklets a professional touch with these Staples black plastic comb binding spins. Group documents together with these comb binding spines. The durable plastic construction stands up to frequent page turns, while the sleek black color adds a perfect finishing touch to marketing materials or presentations. Each spine holds up to 90 pages securely, providing flexible binding options. Compatible with most standard comb binding machines, these Staples binding spines are easy to load and use. These 1/2" plastic binding spines provide a custom look to your official documents. Convenient 90-sheet capacity. Made of plastic in black color. It will not scratch, chip, peel or discolor. Easy to add and remove pages. Compatible with any standard 19-ring comb-binding system. Diameter for this product measures 1/2".