37721 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":36.131775,"wof:name":"37721","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102086455,"postalcode_id":554716977,"region_id":85688701}],"mz:is_deprecated":0,"lbl:latitude":36.11842,"geom:area":0.012783,"geom:longitude":-83.807036,"wof:id":554716977,"counts:concordances_total":1,"geom:type":"Polygon","wof:lastmodified":1611185369,"wof:belongsto":[102191575,85633793,102086455,85688701],"wof:concordances":{"gp:id":"12774086"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"2347601","geom:area_square_m":1.27665437983932E8,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-83.905225,36.069486,-83.717546,36.187665","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-83.812584,"wof:geomhash":"7a59ba984729c57664fd986c6ae08852","wof:parent_id":102086455,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Corryton"}