18915 is a postalcode and its consensus geometry is derived from uszcta.
{"mz:is_ceased":0,"geom:latitude":40.272102,"wof:name":"18915","counts:names_total":0,"wof:placetype":"postalcode","mz:is_current":1,"wof:hierarchy":[{"continent_id":102191575,"country_id":85633793,"county_id":102081355,"localadmin_id":404485463,"postalcode_id":554706067,"region_id":85688481}],"mz:is_deprecated":0,"lbl:latitude":40.272101,"mz:postal_locality_alt":["Montgomeryville","Lansdale","Hatfield"],"geom:area":2.89E-4,"geom:longitude":-75.25683,"wof:id":554706067,"counts:concordances_total":1,"geom:type":"MultiPolygon","wof:lastmodified":1611182713,"wof:belongsto":[102191575,85633793,102081355,404485463,85688481],"wof:concordances":{"gp:id":"12765351"},"wof:repo":"whosonfirst-data-postalcode-us","src:geom":"uszcta","wof:country":"US","counts:names_preferred":0,"gp:parent_id":"2347597","geom:area_square_m":2725037.783356,"wof:tags":[],"counts:names_variant":0,"wof:breaches":[],"edtf:inception":"uuuu","iso:country":"US","counts:names_languages":0,"geom:bbox":"-75.268005,40.258642,-75.243171,40.286468","wof:superseded_by":[],"wof:supersedes":[],"lbl:longitude":-75.25683,"wof:geomhash":"3d6590e3815dd1b22fe0204831cc7176","wof:parent_id":404485463,"wof:placetype_names":["postalcode"],"mz:hierarchy_label":1,"wof:placetype_id":470996387,"edtf:cessation":"uuuu","mz:postal_locality":"Colmar"}