Based on this product's specifications, here are some alternatives and similar models
M6 Cage Nut SCHROFF 21100003 – M6 rack cage nuts, pack of 50
Summary description:
M6 cage nuts by SCHROFF (MPN 21100003) are threaded inserts designed for installing M6 screws into 19" and similar equipment racks and panels. Supplied as a pack of 50, they provide secure and removable mounting for servers, network devices and components. The spring-mounted cage ensures easy insertion into square holes and reliable retention during assembly and maintenance.