57661 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":45.256749,"wof:name":"57661","counts:names_total":0,"wof:placetype":"postalcode","wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102086873,"localadmin_id":404490011,"postalcode_id":554774141,"region_id":85688693}],"mz:is_deprecated":0,"lbl:latitude":45.256752,"geom:area":0.006141,"geom:longitude":-100.960187,"wof:id":554774141,"counts:concordances_total":1,"geom:type":"Polygon","wof:lastmodified":1480912163,"wof:belongsto":[85688693,102191575,404490011,85633793,102086873],"wof:concordances":{"gp:id":"12783041"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"12589865","geom:area_square_m":5.3451358603917E7,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-101.016005,45.207556,-100.843055,45.28496","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-100.960193,"wof:geomhash":"8e3d25d0b764b4ce4d73d674f0bb9228","wof:parent_id":404490011,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu"}