Based on this product's specifications, here are some alternatives and similar models
Binding combs OPUS ib06CZA 6 mm black — document binding spines for punched pages
Summary description:
OPUS binding combs ib06CZA, 6 mm black, are plastic binding spines designed for binding punched pages into notebooks, reports and manuals. Suitable for standard comb binders, they hold a small stack of sheets securely and allow documents to open flat and be edited by removing or adding pages. Ideal for office, school or home document finishing.