These Fellowes Binding Combs will help you to finish your multi-page documents and reports in a professional manner. Each loop has a durable plastic construction and a flexible design making them a versatile option when collating your A4 papers and files. This 10 mm comb size is ideal for securely holding up to 55 pages. They have a plastic Polyvinyl Chloride construction to be durable and long lasting. Each comb has a spine length of 300 mm and a spine size of 10 mm. The 21 loop size is perfect for binding A4 sized reports or similar documents. They're compatible for use with most 21 loop plastic comb binding machines. They can be used to bind 41 - 55 page documents and reports. There are 100 black combs in this pack.