12Pcs Binding Combs: 12Pcs comb binding spines, classic black, sufficient quantity perfect for daily binding notes, documents, reports, etc., providing you with convenience and professionalism Plastic Coil Binding Spines: Comb binding spines are made of high-quality plastic material, soft and tough, flexible to bend, easy to open and close, durable and reusable, can use for a long time 30 Hole Length: Binding coils have 30 hole posts, the total length is 11inch(28cm), you can cut the length according to your needs, it can achieve 30 holes(A4), 26 holes(B5), 20 holes(A5) Widely Applicable: These practical spiral coil binders are spaced approximately 10mm apart, suitable for most binding machines, compatible with 10-hole punches, 20-hole punches, and 30-hole punches Easy To Use: User-friendly design, reopens and closes for easy page addition or removal