https://www.gbceurope.com/en-gb/products/binding-machines--supplies/comb--wire-binding-spines/gbc-wirebind-binding-wires36/
GBC WireBind Binding Wires | GBC
Binding doesn't get any easier! GBC WireBind Binding Wires 3:1 No.4 - A5 White (250) | Colour: black
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