Based on this product's specifications, here are some alternatives and similar models
Staples protective corner pads Prestige A4 3 mm blue pack of 10
Summary description:
Protective corner pads by Staples, Prestige series, sized for A4 documents with 3 mm thickness. The set contains 10 blue corner protectors designed to shield paper, photos or thin boards at corners from bending and wear during storage, transport or filing. Suitable for office, mailing and archival use where corner preservation is needed.