You can use the patented Fastbind Manager Strips with the new generation of Fastbind binders (Secura, Elite and Optima). Fastbind strips allow you to bind with two separate covers (for front and back). You can even create a nice looking binding without any cover.

The three standard sizes allow you to bind up to 0.5˝ (size A), 1˝ (size B) or 1.5˝ (size C) thick, in letter size. They are available in black, dark blue, dark red and white.