Charles Leonard Binder are made up of a sturdy, tempered spring steel construction for flat, or suspended use.Charles Leonard Binder clips are ideal for organizing and filing. Clips are made up of a sturdy, tempered spring steel construction for flat, or suspended use.- Small Binder Clips, 3/4"", 3/8"" Capacity.- Black Tempered Steel.- 12/Box.- Spring steel construction for flat, or suspended use.- Sold as 48/Bundle..