54621 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":43.65802,"wof:name":"54621","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102081733,"localadmin_id":404494103,"postalcode_id":554728479,"region_id":85688517}],"mz:is_deprecated":0,"lbl:latitude":43.656295,"geom:area":0.010933,"geom:longitude":-91.082823,"wof:id":554728479,"counts:concordances_total":1,"geom:type":"Polygon","wof:lastmodified":1611185056,"wof:belongsto":[102191575,85633793,102081733,404494103,85688517],"wof:concordances":{"gp:id":"12781425"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"12590596","geom:area_square_m":9.7801257964363E7,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-91.156779,43.594407,-90.96388,43.723511","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-91.080952,"wof:geomhash":"6e9207704bc48c0fbc6a29078754722e","wof:parent_id":404494103,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Chaseburg"}