EPSG:9401 — El Hierro height

VERTCRS[
    "El Hierro height",
    VDATUM["El Hierro",ID["EPSG",1284]],
    CS[vertical,1,ID["EPSG",6499]],
    AXIS["Gravity-related height (H)",up],
    LENGTHUNIT["metre",1,ID["EPSG",9001]],
    GEOIDMODEL["REGCAN95 to El Hierro height (1)",ID["EPSG",9421]],
    ID["EPSG",9401]
]

+vunits=m +no_defs +type=crs

proj4.defs("EPSG:9401", "+vunits=m +no_defs +type=crs");

{
  "type": "CoordinateReferenceSystem",
  "code": 9401,
  "name": "El Hierro height",
  "kind": "vertical",
  "area": "Spain - Canary Islands - El Hierro",
  "unit": "metre",
  "bbox": [
    27.58,
    -18.22,
    27.9,
    -17.83
  ],
  "proj4": "+vunits=m +no_defs +type=crs"
}

INSERT INTO spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext)
VALUES (9401, 'EPSG', 9401, '+vunits=m +no_defs +type=crs', 'VERT_CS["El Hierro height",VERT_DATUM["El Hierro",2005,AUTHORITY["EPSG","1284"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","9401"]]');

PROJECTION
  "+vunits=m"
  "+no_defs"
  "+type=crs"
END

9401=VERT_CS["El Hierro height",VERT_DATUM["El Hierro",2005,AUTHORITY["EPSG","1284"]],UNIT["metre",1,AUTHORITY["EPSG","9001"]],AXIS["Gravity-related height",UP],AUTHORITY["EPSG","9401"]]