These premium black 1/2" Fellowes double loop wire binding spines are designed for use with the Fellowes Quasar Wire Binding Machine . Still, these 1/2" black elements are also compatible with virtually any other 3:1 pitch twin loop or double loop wire binding system. These black 1/2" spines allow you to quickly and easily create professionally bound reports and presentations. Both durable and elegant, these 1/2" black spines can hold approximately 80-100 pages. Get 25 1/2" black wire binding spines with every order. Product number 5255401.