60551 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":41.525357,"wof:name":"60551","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102081255,"localadmin_id":404498501,"locality_id":85939075,"postalcode_id":554733489,"region_id":85688697}],"mz:is_deprecated":0,"lbl:latitude":41.524931,"geom:area":0.016298,"geom:longitude":-88.684796,"wof:id":554733489,"counts:concordances_total":1,"geom:type":"MultiPolygon","wof:lastmodified":1611184240,"wof:belongsto":[102191575,85633793,102081255,404498501,85939075,85688697],"wof:concordances":{"gp:id":"12784233"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"12588126","geom:area_square_m":1.50879036915605E8,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-88.827404,41.4517,-88.596906,41.589651","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-88.687441,"wof:geomhash":"bfe3636e82003b96612e82a53c37703b","wof:parent_id":85939075,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Sheridan"}