Butterfly binding also calls loop bind. It is similar as saddle stitch except extra 2pcs or 3pcs loops outside the spine. Butterfly binding is a few signature collected in order,staple and there are 2pcs or 3pcs loops outside the spine for user to hold the binder.
Because the 2pcs or 3pcs loops are for holding into the binder. Before doing the butterfly binding, the customer needs to tell the printer what’s your binder size. The printer must follow the customer’s binder size to bind. Otherwise, the final product can’t be used.
In most cases, it is 3pcs loops butterfly binding. The popular binder of two ring distance is 4.291″ between two ring centers.
Except loops binding, the other features are same as saddle stitch. The most pages count of butterfly is also 64 pages.