Amazon.com : 3 Ring Binder, 6 Inch Capacity D Ring Binders, 8.5" x 11" Presentation Folder View Binder with Pockets, Durable Non-Stick Customizable Clear View Cover for Documents, Files, Projects (Black) :
Binder Sizes: A Guide to Standard US 3-Ring Binder Dimensions - Design Resources
Avery Durable 3-ring Legal-size Binders - 2" Binder Capacity - Legal - 8 1/2" Width x 14" Length Sheet Size - 275 Sheet Capacity - 3 x Round Ring Fastener - 2 Pockets - Vinyl, Chipboard - Black - 1 Each