O ring file binder, file accessories O ring binder item: O ring clip material: iron color: nickel/silver, white, gold, black size: inner diameter available: 14.5mm, 19mm, 25mm, 32mm, 38mm, 50mm, 64mm, 76mm, 90mm ring thickness available: 2mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 3mm, 4mm, 4.5mm can be customised